Microbiology facts for kids

An agar plate streaked with microorganisms

Microbiology - (Greek μικρός, mikrós, „tiny“, βίος, bíos, „life“ and λόγος, lógos, „science“) is a science in the composition of biology, which is occupied by the study of microorganisms (bacterium, (archaebacteria), microscopic fungi, protozoa,alga,and viruses). Into the field of the interests of microbiology enter their systematics, morphology, physiology, biochemistry, evolution, role in the ecosystems and also the possibility of practical use. Bacteriology is a division of microbiology.

History

cork Micrographia 1665

In 1665, Robert Hooke saw that cork was made up of little cubes that he named cells. Later Anton van Leeuwenhoek made the important connection that cells are living things when he saw through his early microscope smallest one celled organisms. Later Christian Ehrenberg found that protista or bacteria were different kinds of cells. In the late part of the 1800s Martinus Beijerinck showed that there were small particles called viruses. Another important change in the study of microorganisms came from the discovery of DNA and RNA, because now it is possible to change the inside of a cell without killing it using a vector. One of the most recent discoveries that has changed the study of microbiology is the discovery of transposons or jumping genes. Another one is the discovery of animal genes in the cells.

Applications

Fermenting tanks with yeast being used to brew beer

While some fear microbes due to the association of some microbes with various human diseases, many microbes are also responsible for numerous beneficial processes such as industrial fermentation (e.g. the production of alcohol, vinegar and dairy products), antibiotic production and act as molecular vehicles to transfer DNA to complex organisms such as plants and animals. Scientists have also exploited their knowledge of microbes to produce biotechnologically important enzymes such as Taq polymerase, reporter genes for use in other genetic systems and novel molecular biology techniques such as the yeast two-hybrid system.

Bacteria can be used for the industrial production of amino acids. Corynebacterium glutamicum is one of the most important bacterial species with an annual production of more than two million tons of amino acids, mainly L-glutamate and L-lysine. Since some bacteria have the ability to synthesize antibiotics, they are used for medicinal purposes, such as Streptomyces to make aminoglycoside antibiotics.

A variety of biopolymers, such as polysaccharides, polyesters, and polyamides, are produced by microorganisms. Microorganisms are used for the biotechnological production of biopolymers with tailored properties suitable for high-value medical application such as tissue engineering and drug delivery. Microorganisms are used for the biosynthesis of xanthan, alginate, cellulose, cyanophycin, poly(gamma-glutamic acid), levan, hyaluronic acid, organic acids, oligosaccharides and polysaccharide, and polyhydroxyalkanoates.

Microorganisms are beneficial for microbial biodegradation or bioremediation of domestic, agricultural and industrial wastes and subsurface pollution in soils, sediments and marine environments. The ability of each microorganism to degrade toxic waste depends on the nature of each contaminant. Since sites typically have multiple pollutant types, the most effective approach to microbial biodegradation is to use a mixture of bacterial and fungal species and strains, each specific to the biodegradation of one or more types of contaminants.

Symbiotic microbial communities confer benefits to their human and animal hosts health including aiding digestion, producing beneficial vitamins and amino acids, and suppressing pathogenic microbes. Some benefit may be conferred by eating fermented foods, probiotics (bacteria potentially beneficial to the digestive system) or prebiotics (substances consumed to promote the growth of probiotic microorganisms). The ways the microbiome influences human and animal health, as well as methods to influence the microbiome are active areas of research.

Images for kids

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  Avicenna postulated the existence of microorganisms.

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  Antonie van Leeuwenhoek (1632–1723)

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  Van Leeuwenhoek's microscopes by Henry Baker

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  Martinus Beijerinck is often considered as a founder of virology

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  Innovative laboratory glassware and experimental methods developed by Louis Pasteur and other biologists contributed to the young field of bacteriology in the late 19th century.

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  A university food microbiology laboratory

See also

In Spanish: Microbiología para niños