Bacteria Microbes

Characteristic and Definition of Bacteria

2010-03-03T01:21:00.000-08:00

Bacteria is a single cell and as in general classified into three groups based on the different shape of bacteria. Coccos or spherical, rod or bacillus, spiral or corkscrew (spirochete or spirilla). Some other bacteria have a comma form called as vibrio.

Definition on microbe knowledge:

Aerobic bacteria: this bacteria need oxygen to live
Anaerobic bacteria: is opposite of aerobic, this bacteria don’t need oxygen to live and growth.
Bacillus: bacteria with rodlike shape
Capsule: thick and jelly-like material that surround the surface of some bacteria cell
Decomposers: bacteria breakdown dead organic matter
Fimbriae: short, hairlike projections that may form on the outer surface of a bacteria cell
Fission: a reproduction type in which single cell divides to form two new cells.
Flagella: whiplike projection on the surface of bacteria cells that make movement possible
Pasteurization: a process by which bacteria in food are dead because of food is heated to certain temperature for period of time.
Pili: bacteria join pairs together, make possible to transfer of genetic material between them.
Prokaryote: a cell has no distinct nucleus
Spirilla: bacteria with spiral shape type.
Toxin: poisonous chemical
Vibrio: bacteria with comma-like shape.

As the drawing of anatomy of typical bacterium shows, the cytoplasm of all bacteria is enclosed within a cell membrane that is itself surrounded by a rigid cell wall. Bacteria also produce a thick, jelly-like material on the surface of cell wall.

Other shape like rod, spiral and comma bacteria have whiplike limbs, known as flagella. The function of flagella are for move by waving them back and forth, but for other bacteria are move by simply wiggling their whole cell back and forth.

Bacteria Picture:

Aerobic soil bacterium Pseudomonas Fluorescens.

Anatomy of bacteria:

How To Kill Bacteria

2010-01-19T00:42:00.000-08:00

As may you have known that bacteria is divided into two kind, causes diseases bacteria and harmless bacteria even benefit bacteria. Bacteria can reproduce quickly, Bacteria that can causes diseases called as pathogen bacteria. If we can’t control the bacteria existence, harmful bacteria can take over our home, causing the family be plagued with health problem.

There are several ways to kill bacteria, sterilization uses intense heat, and pasteurization uses mild heat to lessen the number of bacteria in food. Cold temperatures combat bacteria as well. When food is refrigerated of frozen, it is preserved and protected from bacteria. Antiseptic are applied to human skin to eliminate bacteria, disinfectant can be used to clean toilers, sinks, and floors from bacteria.

To omit bacteria from their hand people can washing their hand after using bathroom, touching raw food, changing a baby’s diaper, cleaning up after a pet, or taking out the trash that all of washing use of soap and can also with warm water. Wash process need 15 seconds in order to kill bacteria on the skin.

Kind of antiseptic to kill bacteria also vary, there is a chemical antiseptic like alcohol and other washing substance and there is a plant that can be used as antiseptic like betel leaf. Other way to kill bacteria is to press their enviroment in order can stress the bacteria live, like create an environment that unsuitable with bacteria growth and many other ways.

The Form of Bacteria

2009-12-02T20:45:00.000-08:00

The form of bacteria is vary depend on the kind of bacteria, most of bacteria are on the form of coccus, rod or bacillus and spiral forms.

1. Coccus Bacteria

a. Coccus form of bacteria is a spherical or oval form, this bacteria have on of several distinct arrangement based on their planes of division.
• Diplococcus is arrange in pairs
• Streptococcus is arrange in chain
b. In two planes form produce tetrad arrangement, tetrad is arranged in squared form of 4 angles.
c. In three planes form produce a sarcina arrangement, this bacteria is arranged in cubes with 8 angles.
d. In random planes form produce a staphylococcus arrangement, staphylococcus or cocci arranged in irregular, often grape-like cluster. An average coccus is about 0.5 – 1.0 micrometer in diameter.

2. The rod or bacillus

Bacilli are rod-shaped bacteria. Bacilli all divide in one plane producing a bacillus, streptobacillus, or coccobacillus arrangement.
a. bacillus: single bacilli
b. streptobacillus, a streptobaccillus is arranged in chains
c. coccobacillus, this bacteria form is oval and similar to a coccus
An average bacillus is 0.5-1.0 µm wide by 1.0-4.0 µm long.

3. The spiral
The spirals bacteria come in one of three forms, a vibrio, a spirillum, or a spirochete.
a. vibrio, the form is in curved or comma-shaped rod
b. spirillum, the form is rigid spiral and thick
c. spirochete, this form is thin and flexible spiral The size of spirals range are about 1 µm to over 100 µm in length.

4. Exceptions to the above shapes
Trichome-forming, sheathed, stalked, filamentous, square, star-shaped, spindle-shaped, lobed, and pleomorphic.

Epidemiology: Endemic and Pandemic

2009-10-13T15:34:00.000-07:00

Epidemiology is the study of the distribution and dynamics of disease as it affects large groups of people. Studying disease on the population level is somewhat like trying to solve a large and complicated puzzle, a puzzle that's deadly serious.

Disease: Scope and Statistic
The first question on epidemiologist is likely to ask about a disease is:"How widespread is it?" It may the important to know, for example, whether or not the disease has reached epidemic proportions. An epidemic is said to occur when a disease affect a larger number of people in a certain area that experts would have expected on the basis of previous experience. An epidemic that spreads over huge areas, affecting an entire country or continent, is called pandemic. Diseases that usually occur in just one area as considered endemic to that area. Cholera, for example was endemic to parts of Indonesia for years, but became pandemic when it spread the entire country in 1961.

Next the epidemiologist may need to look at specific statistic that describe heatlh experiences of the population under study, such as:

Mortality rates, the number of death occuring in a given population in a given time period.
Morbidity or incidence rates, the number of new cases diagnosed in those susceptible among a given population.
Life expectancy, the average life span of a person living in a specific population.
Infant mortality, the number of infant who die before age one as a proportion of all live births in the same time period.
Maternal mortality, the number of pregnancy related deaths that occur before, during, and immediately after childbirth among all women aged fifteen to forty four.

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Bacteria Afraid of White Onion or Garlic

2009-08-21T02:39:00.000-07:00

In Indonesia garlic also called as white onion, because similar form and function as ingredient on vegetable cooking. If onion have brown color while garlic is white color. Normally people more use onion on cooking than garlic, but sometime garlic existence is very important like the story below.

Bacteria can grow in many condition except in the condition of over concentration. Bacteria can't grow in the condition of concentrated sugar, concentrated salt or concentrated acid. So many food and forage will treated with this substance to avoid from bacteria growth on the materials.

Surprisingly bacteria also don't like on the material that contains of many garlic substances, on this matter people use garlic to mix with starch on producing fungi seed. Usually the starch usually use from tuber or casava. So not just vampire or dracula who are afraid of Garlic but bacteria also afraid from this substance. Amazing world that garlic can drive away bacteria that contains of garlic. As a single cell bacteria very sensitive to certain material and won't grow on that condition.

By mixing a starch with garlic, then will grow a fungi instead of. This fungi seed then screen to select a certain fungi and create a pure of certain fungi. After the starch grow just with a certain fungi, people faded this bacteria and can produce it and dupicated as many as they want. From just a small peace of fungi seed people can produce thousand of other fungi seed, this method can use for money make machine. Actually bacteria also useful on other kind of process, not all kind of bacteria unuseful, for certain purposes people also use of certain kind of bacteria to help them on getting their purposes.

Faded Bacteria Disease

2009-07-29T00:17:00.000-07:00

Faded bacterial disease is one of the important diseases in the patchouli in West Sumatra, North Sumatra, and Nanggroe Aceh Darussalam (NAD). The disease is caused by the Ralstonia solanacearum bacterium and can reduce production of patchouli until 60% to 80% so that become a constraint in increasing of patchouli product. Pathogenic control can be done by using resistant varieties, namely Sidikalang, cultivation techniques (fertilization, organic, and mulsa), biological pesticides (Pseudomonas fluorescens and Bacillus spp.), Vegetable pesticide (Serai), chemical control (bakterisida), and limit the spread of pathogenic from infected areas to other areas.

To control of fading bacterial diseases must be conducted with the integrated control combining various techniques. Patchouli commodity (Pogostemon cablin Benth) is an important export commodity in Indonesia. Patchouli oil exports reached 1,276 tons with a value of U.S. $ 19,264 million (Directorate General of Agriculture 2006). Indonesian patchouli oil is the largest exporter in the world to supply nearly 90% of the world needs of patchouli oil (Asman 1996). Therefore, the patchouli oil is expected to increase sources of income from the state sector non fuel and gas.

Patchouli oil has a good prospects to meet the needs of perfume and cosmetics industry. Patchouli oil can also be used as an antiseptic, insecticide, and aromatherapy. Patchouli alcohol is the main components of patchouli oil and is used as an indicator of patchouli oil quality.

One of the diseases causes among other is faded disease bacteria which can reduce production from 60% to 80% (Asman et al. 1993). This disease has spread to almost all patchouli production centers in West Sumatra, NAD, and North Sumatra, even of late have been found in West Java and central Java. This faded bacteria also attack other young plant like papaya, tomato, spinach, potato and other vegetable plant.

Bacteria to Produce Hyaluronic Acid

2009-07-05T21:58:00.000-07:00

Production Story:
The production of Hyaluronic acid using of Semi continuous cultivation of Streptococcus Zooepidemicus bacteria, a culture will ensure the availability of raw materials on an on going basis, also if bacteria being cultivate then will be able to provide the needs of various industrial medicine raw material. People who is growing old, will produce elastic cell lessen than young people. So the skin will look wrinkle for old people after their skin change, especially when the skin wide then change to narrow, also if the person is fat then growing to lean at last. The skin can’t back to normal again and look wrinkle. Especially for women, not like this happened, become minder and afraid if appear not in beautiful looking.

Useful:
Hyaluronic acid is one of the most drugs used as skin filler, which functions together with the collagen and elastin in the skin wrinkling problem. Hialuronic acid will react with water and fold easily fill the skin around the mouth and cheek.

Skin wrinkled will lost soon after injection process is finished. One of the benefits of acid hyaluronic gel have lessen of allergic reactions if compared with collagen. By using network cultures of microorganisms Streptococcus bacteria zooepidemicus, hyaluronic acid production done in a semi-continuous, with the condition cultivation in maintaining temperature and speed and made repeatedly.

Bacteria Growth

2009-07-05T19:39:00.000-07:00

Bacterial organisms are the most in number and more widespread than any other organism. Hundreds thousands of bacterial species that live on land and sea also in extreme places.

Bacteria have a beneficial but there are also harmful. Bacteria have characteristics that distinguish it with another living organism. Bacteria are organisms unicellular and prokaryotic and generally do not have chlorophyll and micro size (microscopic).

The characteristics of bacteria
Bacteria have characteristics that different with another organism such as:

Organisms multi-cellular
Prokaryote (do not have the core of the cell membrane)
Generally do not have chlorophyll
Body size that varies between 0.12 up to hundreds of micron size generally have an average of 1 s / d 5 micron.
Have varies form of body
Free living or parasitic
Who live in extreme environments such as hot water in the eyes, mouth or turf cells wall does not contain peptide
The cosmopolitan life in different environments cell wall contains peptide.

Structure of Bacteria
Structure divided into two bacteria, namely:

Basic structure (owned by nearly all types of bacteria), Include: cell wall, plasma membrane, cytoplasm, ribosome, DNA, and storage granular
Additional structure (owned by a certain type of bacteria).

Includes capsule, flagellum, Piles, fibrin, chloroform, Vacuole gas and endosperm.

Bacteria Forms:
Basic form of the bacteria is made up of rounded form (cocus), rod (bacillus) and spiral (spirilia) and there is a form of cocus and basil called coco-bacillus.
Many forms of bacteria:

Coccus:

Monococcus, the form of single cell bacteria coccus
Diplococcus, the two bacterial cell unite
Tetracoccus, the four bacterial coccus cells unite to form quadrangular.
Sarkina the eight bacterial coccus cells unite to form cubes
Streptococcus of more than four coccus cells unite to form chains.
Stapilokokus of more than four coccus bacterial cells unite such as grape

Bacillus Bacteria:

Mono bacillus, the form of single cell bacteria bacillus
Diplobacillus the form of two-cell bacteria bacillus unite
Streptobacillus that some bacteria cells unite establish germ like chain

Spirally Bacteria:

The form of a spiral-wave cell
Spirochete the form of cells, such as the screw
Vibrato cells that form of punctuation such as commas

Infected by E. Choli Bacteria

2009-06-02T02:14:00.001-07:00

Be careful for someone who work with contact regularly with waste, especially with domestic waste, because this bacteria usually exist on this area. Escheriachia choli, salmonella and campylobacter are exist on this waste, and if infected to human body can cause illness.

Sometimes attributed to "food poisoning" or called, "stomach flu", gastroenteritis pertains to the irritation and inflammation of the gastrointestinal tract which consists of the stomach and the intestines. Because this is usually caused by infections, its severity can be related to your ability to combat infection. Some people tend to recover from this illness faster than others. Also, since people who experience this ailment tend to excrete a lot of fluids either through vomiting or loose bowel movement, there is a danger of losing electrolytes and becoming prone to dehydration which is a life-threatening illness.

The most common causes of gastroenteritis is the presence of viruses and bacteria. Both may enter your body from the food you eat or contact with other people who have the illness. Also, these infectious agents can be caused by something in your body if you have an abnormal condition. This can happen when you drink antacids or any medication that can alter the acidity of your stomach.

Escherichia coli, also known as Traveler's diarrhea, can come from unclean food and water. Salmonella, on the other hand, is more dangerous because it causes typhoid fever. It can be acquired from holding poultry or reptiles that have a lot of germs. Campylobacter can enter your body through undercooked meat and un-pasteurized milk.

When the gastroenteritis is caused by a virus, then it will only take 1 to 2 days to recover from it. 30 to 40% of the viral cases of gastroenteritis usually involve children. Because of the close contact between children in daycare and pre-schools, the spread of this virus can be quite fast. The common viruses that cause gastroenteritis are: adenoviruses, rotaviruses, calciviruses, astroviruses and norvirus.

Other causes of gastroenteritis are parasites and protozoan’s. These organisms may enter your body by drinking contaminated water. Toxins that can be found in sea food, heavy metals and medications can also be te cause of gastroenteritis.

A person suffering from gastroenteritis commonly experiences a low grade fever that is accompanied by nausea with or without vomiting and mild to moderate diahrrea which means that the patient will release two to four loose stools per day. The patient will also experience some cramps and bloating. These symptoms can be alleviated by rest and the replenishment of fluids.

Unfortunately, gastroenteritis can also be accompanied by serious symptoms that need medical attention. One of them is having a fever that is higher than 101 degrees Farenheit or 38 degree C. This makes monitoring the patient's temperature very important. Other symptoms that require medical care are spots of blood in the vomit or stool, swelling or pain in the right lower part of the abdomen and dehydration which can be monitored by knowing the frequency of the patient’s urination.

To someone who indicate infected by this bacteria better consult to doctor and discuss precisely about the illness in order the doctor can give an exact advise and take the right action for your diseases.

Streptococcal Infection

2009-04-17T09:49:00.000-07:00

Streptococcal bacteria, small inhabit out mucous that grow in long chains, usually inhabit our mucous membranes, particularly those of the nose, mouth, throat, and intestines. If our resistance is lowered, they may cause diseases such as “strep throat” (a severe throat infection), peritonitis (severe inflammation within the abdomen), and scarlet fever (an acute fever with sore throat and rash), or rheumatic fever (an infection that primarily affects the joints and the heart). Streptococcal infections often produce spreading inflammation throughout the body.

Other streptococci may be introduced from outside the body, and this was once the cause of many cases of “childbed fever,” which killed many new mother in centuries past. Two streptococci in this instance were introduced by the infected hands of the doctor or other attendant at childbirth.

Staphylococcal Infections
Staphylococcal which grow in small clusters are normally present on our skin, and most of the time they live there harmlessly. Occasionally, however, if there is a scratch or other small opening in the skin, the staphylococci will get in. They usually produce a localized infection, in contrast to the widespread infections often caused by streptococci. All of us who have had pimples on the skin have had minor staphylococci (“staph”) infections, and staphylococci are also the cause of more serious infections, such as boils (in which the organisms penetrate the skin more deeply) and styes (infections on the eyelids). When a cut or wound becomes infected, the invading organisms are likely to be staphylococci. The redness and soreness around the cut are the results of the body’s defense against the infection.

BACTERIAL TOXINS

2009-03-01T18:31:00.000-08:00

As we mentioned, the symptoms in TSS (Toxic shock Syndrome) are caused by toxins (poisonous substances) that the bacteria produce. Certain other bacteria also produce dangerous toxins. The tiny botulinus bacterium is another example. This organism is harmless when it’s eaten; it’s often present on food. But if it is growing in a place where there is low acidity and little or no oxygen (inside a sealed can, for example), it stars to produce a toxin would be enough to kill everyone on earth.

During the period shown, 1,660 cases of toxic shock syndrome were reported, mostly among white women of menstruating age. The incidence of TSS began to decline in 1981, possible because more women heeded warning to stop using super absorbent tampons and to alternate tampons with sanitary napkins during their periods, to discourage the growth of bacteria.

WHAT YOU CAN DO TOXIC SHOCK SYNDROME (TSS)

Everyone should know the symptoms of TSS; headache, sore throat, fever, abdominal pain, diarrhea, Vomiting, sometimes a rash. Millions of woman have used tampons for years without developing the disease, but women who want to avoid even the small risk of developing TSS may want to avoid tampons or to use them during only part of their menstrual periods.

EXOGENOUS BACTERIA AND DISEASE

2009-02-18T07:30:00.000-08:00

A number of major diseases are caused by exogenous bacteria-gonorrhea, meningitis, tetanus, and syphilis, to name just a few. Some of these are being brought under control, thanks to antibiotics –a group of drugs that destroy or inhibit the growth of diseases –causing bacteria . The bacterium that causes tuberculosis is an example ; in the 1930s about 80% of all Americans became invented with it before they were twenty years old , but today less than 5% become infected in most parts of the U.S. though there has been an upsurge of the disease in some metropolitan areas.

Legionella pnemophila is another example : once expert figured out the link between this microbe and Legionnaire’s disease, they determined that it could be controlled with the antibiotic erythromycin.

But there is an ominous new trend : many bacteria have now developed resistance to antibiotics, About forty times as much penicillin is needed now to treat some infections as was needed when the drug was treat some infections as was needed when the drug was first used during World War II. Ominous, too, is the recent upsurge in certain bacterial sexually transmitted diseases, some of which are resistant to antibiotics .

Agents of Infection and Some Diseases

2009-01-31T09:32:00.001-08:00

Like the natural world around you, your own body is part of the environment. You’re the host to countless tiny animal organisms and plantlike organisms, plus some that are neither animals nor plants, all living together in your body and carrying out their own basic life functions of respiration, metabolism, excretion, growth and reproduction.

Six categories of these organisms can become pathogens, or agents of infections disease: bacteria, viruses, ricketisiae, fungi, protozoa, and worms.

Bacteria
Most plentiful of the microorganisms endogenous to humans are the various kinds of bacteria (singular: bacterium). Each of these tiny organisms consists of just one cell, with a protective cell wall and all the structures it needs to carry out its life functions. The bacteria fall into the category of flora or plantlike organisms.

Endogenous Bacteria and Disease
Most kinds of endogenous bacteria are not harmful, and some, in fact, are vital to our existence. The bacterium Excherichia colli (often calle E. Coli), for example, lives in our intestines and is essential to the synthesis of the B vitamins, others help to kill off foreign infectious organisms. But our own endogenous bacteria can cause disease if for some reason they get out of hand. Skin bacteria sometimes cause aene; mouth bacteria sometimes help cause pyorrhea, a serous gum disease: intestinal bacteria may get into the urethra, particularly in a woman, and cause urinary tract infections. Different strains of E.colli, which we may be exposed to through travel, may cause diarrhea until our system adjust to their presence.

Paramecium

2008-12-08T07:23:00.000-08:00

Paramecium is a genus of single-celled protozoans with cilia, in the class Ciliophora. Found free living in fresh water, paramecia are easily recognized under the microscope by their distinctive slipper shape. The body surface is covered with numerous cilia used for the organism’s spiraling locomotion. The water currents thus produced help funnel bacteria, the paramecium’s usual food, into the mouth, which is situated at the end of the oral groove, a ciliated channel. A food vacuole forms around the food and travels in a cyclic manner in the cytoplasm. The vacuole’s contents are subjected to digestive enzymes, and the products of digestion are diffused into the cytoplasm. Undigested material is released at the posterior end of through several permanently located contractile vacuoles, which produce star-shaped tubes in the water collecting process.

Sexual reproduction in Paramecium is achieved through an exchange of chromosome containing nuclei between two temporarily united paramecia. Genetic characters are passed to offspring by nuclear reorganization and duplication followed by a simple pinching into two cells. Paramecia also reproduce asexually through binary fission.

Paramecium Caudatum, only peripheral cilia are shown, for charity. cv, contractile vauole; fv, food vacuole; m, micronucleus; N, macronucleus; OG, oral groove; Ps pristome (vuccal cavity); cs, cytosome; ffv, forming food facuole.

Algae

2008-11-15T04:25:00.000-08:00

Algae are a very diverse group of photosynthetic organisms that range from microscopic size to giant kelp that may reach lengths of 20 m (66 ft). Some commercial biochemicals come from algal seaweeds, and algae supply oxygen and consume nutrients in some processes used for biological waste treatment.

Although their rapid growth rates relative to other green plants offer great potential for producing biomass for energy or a chemical feedstock, there is little industrial use of algae. One proposed process uses Dunaliella, a species that grows in high salinity and accumulates glycerol internally to counter the high external osmotic pressure. Outdoor ponds are most suitable for growing algae because vast surfaces and high illumination are needed.

Fungi As a group, fungi are characterized by simple vegetative bodies from which reproductive structures are elaborated. All fungal cells possess distinct nuclei and produce spores in specialized fruiting bodies at some stage in their life cycles. The fungi contain no chlorophyll and therefore require sources of complex organic molecules for growth: Many species grow on dead organic material; others live as parasites.

Yeasts are one kind of fungi. They are unicellular organisms surrounded by a cell wall and possessing a distinct nucleus. With very few exceptions, yeasts reproduce by a process known as budding, where a small new cell is pinched off the parent cell. Under certain conditions, an individual yeast cell may become a fruiting body, producing spores.

Isolated Plant and Animal Cells Biotechnology includes recovery of biochemicals from intact animals and plants, but the care and feeding of them is beyond the scope of this section. Processes with their isolated cells have much in common with processes based on microorganisms. The cells tend to be much more fragile than microbial cells, and allowable ranges of pH and temperature are quite narrow. These cells occur in aggregates and usually require enzymes to free them. There is a strong tendency for the cells to attach to something, and cell cultures often exploit attachment to surfaces.

Plant and animal cells have numerous chromosomes. Growth rates are relatively slow. A typical nutrient medium will contain a large number of vitamins and growth factors in addition to complex nitrogen sources, because other specialized cells in the original structures supply these needs. A plant or animal cell is not like a microbial cell in its ability to function independently.

Bacteria as Single Cell

2008-11-10T17:49:00.001-08:00

The bacteria are tiny single-cell organisms ranging from 0.5–20 mm in size, although some may be smaller, and a few exceed 100 mm in length. The cell wall imparts a characteristic round or ovoid, rod, or spiral shape to the cell. Some bacteria can vary in shape, depending on culture conditions; this is termed pleomorphism. Certain species are further characterized by the arrangement of cells in clusters, chains, or discrete packets.

Some cells produce various pigments that impart a characteristic color to bacterial colonies. The cytoplasm of bacteria may also contain numerous granules of storage materials such as carbohydrates and lipids. Bacteria can contain plasmids that are pieces of genetic material existing outside the main genome. Plasmids can be used as vectors for introducing foreign genes into the bacteria that can impart new synthetic capabilities to an otherwise “wild” bacterial strain. Many bacteria exhibit motility by means of one or more hairlike appendages called flagella. Bacteria reproduce by dividing into equal parts, a process termed binary fission.

Under adverse conditions, certain microorganisms produce spores that germinate upon return to a favorable environment. Spores are a particularly stable form or state of bacteria that may survive dryness and temperature extremes. Some microorganisms form spores at a stage in their normal life cycle.

Many species may, under appropriate circumstances, become surrounded by gelatinous material that provides a means of attachment and some protection from other organisms. If many cells share the same gelatinous covering, it is called a slime; otherwise each is said to have a capsule.

BACTERIA AND DISEASE

2008-11-05T00:53:00.000-08:00

A century ago in the United State and even today in the less developed countries, at least 25% of the children died of bacteria infections before reaching puberty. In the united states and other Western nations, this figure is now below 5% as a result of improved sanitation, hygiene, and medical care.

The control of Typhoid fever alone is perhaps the greatest triumph of organized preventive medicine. As late as 1900 the annual death rate from typhoid fever in United States was more 30 per 100, 000; by 1944 the rate hade decreased to 0,4 per 100, 000.

For the world as the whole however, typhoid fever remain a major disease.

History.

To account for the spread of certain disease, thoughtful people since ancient times postulated the existence of transmissible agents of infections invisible to the naked eye, In 1546 the Italian physician Girolamo fracastoro proposed the germ theory of disease, describing the transmission of disease by ‘Seminaria’ or living germ. Visualization of germ could not take place until the microscope had been invented. However, bacteria and other microscopic organism were first seen in 1676 by a Dutch linen-draper, Antony Van Leeuwenhoek, who made single lens microscope with sufficient magnification to observe the major types of bacteria as well as protozoans, yeasts, and one-celled algae. Leeuwenhoek is regarded as the father of bacteriology.

The first important classification of bacteria was made in the early 1800s. In 1829, Christian Gottfried established the genus Bacterium, using a term formed from the greek word Bacterion , signifying a rod.

The entire subject of bacteriology has taken its common name from the prominence of rodlike forms of bacteria, now called bacilli. Eventually, bacteria were classified as plants; this remained the dominant view until the 1960s. Bacteria are now clasisified as Monerans.

An experimental science of bacteriology emerged slowly and required the development of special methodology. The key was the use of sterile (germ-free) materials and antiseptic technique; a singe contaminating cell can ruin an experiment in bacteriology. Only after learning to avoid such contamination could investigators recognized the existing variety of bacteria, their distribution, and their major rules.

ECONOMIC IMPORTANCE OF BACTERIA

2008-10-31T20:08:00.001-07:00

Most importance bacteria are harmless to humans, and many bacteria are essential or useful to the existence of plant and animal life. Only a small fractions of bacteria causes disease; most bacteria attack organic matter only after it is dead. Were it not for bacteria that decomposed animals and plants. These material would accumulate almost indefinitely.

Bacteria also enrich the soil in various ways. The so-called nitrogen fixing bacteria take nitrogen gas fro the atmosphere and convert it to a form (nitrate) that green plants use for growth. Bacteria also create fertilizer by breaking down compost heaps made of soil and dead plat matter.

Bacteria are important industrially in the production of cheese, yogurt, buttermilk, vinegar, and sauerkraut; in the preparations of antibiotic such as streptomycin, which is extracted from soil bacteria; in the tanning of leather and hides and the curing of tobacco; and in the sewage disposal plants to render organic wastes harmless. Cattle, sheep, and goats live on the grass; yet without bacteria they would not be able to digest the tough fibers of plant cellulose.

Improperly processed foods are subject to spoilage by bacteria. Poisonous toxins are sometimes produced by such spoiling bacteria as staphylococci, Streptococci, and Salmonella. They cause severe illness human eating affected food. Clostridium botolinum, growing in canned or smoked foods that have been improperly processed, produces a toxin that causes Botulism, frequenly fatal disease.

BACTERIAL SENSITIVITY

2008-10-26T04:57:00.000-07:00

The susceptibility of a given bacterial species to an antibiotic is usually determined either from laboratory tests or from the result of treating an establish ed infection.

In laboratory tests, bacteria isolated from an infected patient are inoculated into tubes containing a liquid culture medium enriched with graded concentration of an antibiotic agent. The lowest concentration of antibiotic that inhibit microbial growth is termed the minimal inhibitory concentration (MIC). When this is compared with concentrations attainable in the body, one can judge whether the bacteria are sensitive, partly sensitive, or resistant to the antibiotic.

Alternatively, the surface of a semisolid growth medium can be inoculated with bacteria, and antibiotic-impregnated filter-paper disks placed on that surface. The antibiotic leaves clear zones around habited. The diameter of the inhibitory zones can be measured accurately and the results precisely interpreted.

Occasionally such tests do not correlate with clinical results, particularly when a person has a malignant disease, immune-system impairment, or severe injury, or is receiving drugs that reduce resistance to infection. Outcome may also be unpredictable because of failure to absorb the antibiotic, deterioration of the antibiotic during storage, or its inactivation by simultaneously administered drugs.

CLASSIFICATION OF ANTIBIOTIC

2008-10-24T22:08:00.000-07:00

The most common classification is based on mechanism of action. Antibiotics that inhibit the growth of the bacterial cell wall include the commonly used penicillin and cephalothin groups, and such less-often-used antibiotics as vaconmycin and bacitracin. Antibiotic that act like detergent on the cell membrane-and therefore disrupt the passage of nutrients into the bacterial cell-include the antibacterial polymycin and colistin, and the antifungals mycostatin and amphotericin .

Antibiotics that interfere with protein synthesis in the bacterial cell include the tetracycline, the aminoglycosides (streptomycin, kanamycin, neomycin, gentamycin, amikacin) and the macrolide group comprising erythromycin, licomycin , and climdamycin.

Antibacterials that disrupt bacterial gene replication include the antifungal griseofulvin to kill a fungi and the synthetic quinolone drugs.

Bactericidal and Bacteriostatic Effect

Another classification system is based on whether an antibiotic kills microorganism (bacterial effect) or merely inhibits growth (bacteriostatic effect). Penicillins, aminoglycoside, vanconmycin, bacitracin , the polymyxin, and colistin are bactericidal. Tetracyline, on the other hand, is bacteriostatic. When susceptible bacteria are exposed to tetracycline, growth will cease temporally and then resume.

Chlorophenicol and the macrolides are also bacteriostatic. Lethal infectious diseases will respond only to bactericidal agents.

Spectrum of Activity

A further classification system rests on the effective target range (activity spectrum) of an antibiotic, as defined by two criteria;

The species of susceptible microorganism (for example, staphylococcus, streptococcus, and E coli)
Weather the species are gram-positive or gram-negative.

Bacteria retaining a blue stain despite treatment with iodine and acid alcohol are called gram-positive, and those losing it are gram negative.

The penicillin are effective against most gram-positive bacteria, whereas aminoglycosides are chiefly effective against gram-negative bacteria. These two groups of antibiotics are therefore termed narrow-spectrum agents.

Tetracycline and chlorophenicol are effective agains a broad range of gram positive and gram negative bacteria, rickettsia, and other microorganism and are therefore called broad-spectrum antibiotics.

Bacteria Identification

2008-10-24T06:51:00.000-07:00

Bacteria Identification is a special technique that is used by biologist and many other scientist, because many of bacteria is useful for human, beside the others can disadvantage for human. Beside can cause diseases, many bacteria type is need by human for food process or industrial uses. To make sure that the bacteria can useful for certain application, people must identify the bacteria that want to use.

An important, widely used technique for identifying bacteria is gram staining, perfected by the Danish bacteriologist Hans Christian Gram in 1884. In this process the bacteria are treated with a special dye, or stain, and other chemicals. The treated this microbe, bacteria fall into two groups, gram-positive bacteria, which appear deep violet in color. and gram-negative bacteria, which appear red in color. Physicians often use gram staining in choosing the proper Antibiotics for treating a bacterial infection. Gram-positive bacteria are more susceptible to penicilin, whereas gram-negative bacteria are usually more susceptible to other antibiotics such as streptomycin. The basis of this difference in staining properties is still a mystery, but evidence indicates that the difference lies in the composition of the bacterial cell wall.

Although bacterial and plant cells are enclosed by rigid walls, the walls differ in composition. Plant cell walls derive their strength largely from cellulose, whereas bacterial cell walls are stiffened primarily by murein (a compound made of amino acids and sugar). This is the basis for the selective activity of certain drugs such as penicilin. Nontoxic to plants and animals, penicilin is toxic to habitat growing of bacteria because it inhibits formation of murein and thus interferes with reproduction.

The Useful of Bacteria

2008-10-15T00:30:00.000-07:00

There are two kind bacteria if see from the uses for human, benefit and disadvantage for human. Most of us think of bacteria as "germs" or microorganism, unseen threats to our health and welfare. But for each of the few disease-producing kinds which can live in the human body, there are hundreds of others upon which we depend for our very existence. Bacteria help us digest our food. Plant will die if no bacteria to convert leaf or other organic matter to humus.

Most kinds multiply by simply splitting in two: each bacterium dividing into two equal "daughter" bacteria every 20 or 30 minutes, under favorable conditions. Though microscopic in size, they can multiply so fast that, after a day and a half, the billions of offspring of a single one would load a long freight. Under unfavorable conditions, some kinds form thick-walled spores which can withstand prolonged drying, extreme cold, and even boiling; and may lie inactive for days or even years.

All animals depend upon plants, directly or indirectly. Plants depend upon the fertility of the soil, which in turn depends upon bacteria. Inconceivable numbers of them inhabit the soil -- roughly a billion per teaspoonful -- where some convert plant and animal remains into humus and plant food, and others make the minerals in the soil available as plant food. All decomposition and decay in the dead bodies of plants and animals are caused by bacteria and their close relatives: molds, fungi and yeasts. Our huge garbage dumps are decomposed by them. Our modern methods of sewage disposal employ speeded-up bacterial action to rapidly break down and oxidize household and industrial wastes.

Some of plant reside a kind of bacteria, Nitrogen in the form of nitrates is an essential plant food frequently lacking in soils. Nitrogen from the air is inert and difficult to change and combine with other substances, but certain bacteria have the rare ability to absorb it and change it into forms which other plants and animals can use.

Fermentation, as when wine and cider turn into vinegar, is caused by bacteria. Of hundreds of different kinds, a few of the common bacteria are those used to make rye bread, sauerkraut from cabbage, pickles from cucumbers, silage from corn, linen from flax, glycerin, citric acid, lactic acid, and dairy products.

Fresh warm milk is an ideal food for many kinds of bacteria, especially the common one which causes milk to sour and curdle. Cream so soured and ripened is easily churned into butter. Cottage cheese is made from sour milk. Most cheeses are made from curds produced by treating milk from cows, sheep or goats with "rennet", a digestive ferment. The ripening, and the different textures and flavors, are accomplished by various pure cultures of bacteria and molds which are added to the curd as "starters", depending also upon special conditions of air, moisture and temperature. Some extremely hard Italian cheeses contain little water and are correspondingly slow to ripen. "Soft" cheeses contain more water and ripen more rapidly. The blue-green mold of Roquefort is due to powdered bread mold sifted into the curd. The holes in Swiss cheese come from gas generated by bacteria.

Size and Habitat

2008-10-06T05:45:00.000-07:00

Thirty trillion bacteria of average size weigh about 28 g (1 oz). Bacteria are measured in microns (0.001 micrometer, about 0.00004 in) and most types range from 0.1 to 4.0 microns in width and 0.2 to 50 microns in length. Bacteria are found every where. Approximately 2,000 species have been identified, many of them living in conditions that would destroy other organisms. They have been found in the almost airless reaches of the upper atmosphere, 10 km (6 mi) below the surface of the ocean, in frozen soil, and on rocks in hot springs. Some bacteria produce a resting stage, the endospore, which is the most resistant living thing known and can be killed only by boiling in steam under pressure for many hours.

Classification
Bacteria are neither plant nor animal. Both bacteria and plants have rigid cell walls, but unlike plants, most kinds of bacteria move about and use organic foods for energy and growth; only a few use photosynthesis.

On the basis of their shapes, bacteria may be grouped into three main type; the rod-shaped bacilli, which often have small whiplike structures known as Flagella that propel the organism; the spherical cocci (singular coccus), which may grow in chains (streptococci, or strep germs," as in strep throat) or which may clump together like a bunch of grapes Istrphylococci); and the comma or spiral shape spirilla and prirochetes (one of which is the cause of syphilis). Another kind of bacteria, the mycoplasmas, have no rigid cell walls and consequently are called pleuropneumonialike organisms, because they cause a contagious pneumonia in cows and human beings.

Bacteria as Part of Microorganisma

2008-09-26T05:14:00.000-07:00

Microorganisma is a large group that is included bacteria, viruses, spores and others micro creature. A large group of prokaryotic microorganism characterized by multiplying via fission or forming spores, and generally lacking chlorophyll or distinct nucleus surrounded by a membrane. Bacteria furnish both the raw material and the chemical machinery for their own reproduction, whereas viruses, for example do not.

Bacteria is constitute one of division in the kingdom Monera. Bacteria are unicellular and often classified by shape and may be spherical, spiral, rodlike, or coma shaped. They may be saprophytic (bacteria are the major the composers in most ecosystem), parasitic (such as those causing diseases such as pneumonia or typhoid fever), or auto-trophic (hydrogen sulfide bacteria).

The oldest sign of life is a fossilized bacteria cell discovered in a rock in Africa and estimated at about 3.5 billion years old.

The study of bacteria is called bacteriology, which belongs to the broader science of MICROBIOLOGY, or the study of all types of microorganism , including one-celled protozoan, yeast, and algae.

Medical microbiology is concerned with the behavior and control of pathogens, which are microorganisms that cause infectious DISEASES in human and other animals.

Bacteria as part of Microba

2008-09-19T03:06:00.001-07:00

Bacteria is the common name for a vast group of one celled microscopic organisms that encompasses the smallest, simplest, and perhaps first form of cell life that evolved. They constitute one of two divisions in the kingdom Monera. Bacteria furnish both the raw material and the chemical machinery for their own reproduction, whereas viruses, for example, do not. The oldest sign of life is a fossilized bacterial at about 3.5 billion years old.

The study of bacteria is called bacteriology, which belongs to the broader is called bacteriology, or the study of all types of microorganisms, including one celled protozoans, yeast, and algae. Medical microbiology is concerned with the behavior and control of pathogens, which are microorganisms that cause infections Diseases in humans and others animals.