Work-Principle of microbiology

Diversity of Bacteria- Gram Positive Bacteria

1. Firmicutes: A phylum of bacteria with Gram positive cell walls and low DNA G+C  contents. The name of this group means those with firm envelopes.

2. Actinobacteria: Antoher group of bacteria having Gram positive cell walls but with high DNA G+C contents. The name of this group means bacteria growing as filamentous forms.
Actino-: ray, beam

3. Lactobacillus: Typically rod-shaped and grow in chains, varying from long and slender to short, bent rods, and nost are homofermentative, common in dairy products.

4. Streptoccocus: The genus play important roles in the production of buttermilk, silage, and other fermented products, and certain species paly a major role in the formation of dental caries. There are several other genera of homofermentative.

*Dental cries: tooth dacay

*Silage:preserved pasture.

*Homofermentative: Producing a fermentation resulting wholly or pricipally in a single end product.

* fermentation: Chemical process by which molecules such as glucose are broken down anaerobically.

5. The genus Lactococcus contains of dairy significance, wherease the genus Enterococcus that are primarily of fecal orgin and can be human pathogens.

6. Lactic acid bacteria can be classified into two groups depending on the final products of lactic acid fermentation.: Homofermentative group and Heterofermentative group.

7. Listeria monocytogenes: A species of Gram positive bacteria which is a causative agent of listeriosis. The generic name was named after a surgeon, Joseph Lister.

8. Staphylococcus aureus: A species of Gram positive bacteria which is one of the most common inhabitants of human body, and also a common cause of skin infections. The generic name means a bunch of grapes, and the species name golden color.

* Staphylococcus: faculataive aerobe, catalase-positive, gram-positive coccus.

9. Sarcina: Obligate anaerobic, catalase negative and extremly acid tolerant genus belonging to the clostriudium familay(Clostridiaceae). the name means a package or bundle, and the genus was recently reclassified as members of Clostridium.

*Catalase: a common enzyme found in nearly all living organisms exposed to oxygen. It catalyzes the decomposition of hydrogen peroxide to water and oxygen.

10. Bacillus thruingiensis, Paenibacillus popilliae: known to produce insect larvicide crystals in their endospores.

* larvicide: insecticide that is specifically targeted against the larval life stage of an insect.

11. Stickland reactions: A fermentative metabolism of some members of Clostridium, an obligate anaerobic genus, in which a pair of amino acids are used. One serves as an electron donor, and the other as an electron acceptor.

12. Mycoplasma: A genus of Tenericutes(having soft cell enevelope), lacking cell walls, and growing in pleomorphic forms. One of the smallest organisms capable of autonomous growth, and parasitic to animal and plant hosts.

13. Spiroplasma: The genus consists of helical or spiral-shaped. Although they lack a cell wall and flagella. They have rotary screw motility. The organism has benn isolated from ticks, the hemolymph and gut of insects, vascular plant fluids and insects that feed on these fluids, and the surfaces of flowers and other plant parts.

14. Arthrobacter: The genus consisting primarily of soil organisms. They are remarkably resisant to desiccation and starvation, despite the fact that they do not form spores or other resting cells.

15. Propionibacterium: An actinobacterial genus famous for the association with Swiss type chesses. Performs secondary fermentation, which is the fermentation of substrates produced from another fermentation by other bacteria.

16. Corynebacterium glutamicum: An actinobacterial species known to produce glutamic acid. The genus to which this species belongs is characterized by club-shaped, irregularly shpaed, aor V-shaped cell arranagements of cells.

* Glutamic acid: an alpha-amino acid that is used by almost all living beings in the biosynthesis of proteins.

17. Mycobacterium: An acid-fast actinobacterial genus forming tight, compact, wrinkled colonies due to the presence of mycolic acids. Includes pathogens of tuberculosis and leprosy.

* mycolic acids: long fatty acids found in the cell walls

18. Streptomyces: The largest prokaryotic genus blonging to actinobacteria, forming extensively branching aerial and substrate mycelium. The genus is also famous for the production of secondary metabolites, notably antibiotics by many members.

*mycelium: vegetative part of a fungus or fungus like bacterial colony.