BASIC SHAPES OF EUBACTERIA SPHERICAL ROD-SHAPED SPIRILLA

Most Species of bacteria may be Grouped Based on Staining Gram-Negative –Lack thicker layer of peptidoglycan –Stain pink –Endotoxins Gram-Positive –Thicker layer of peptidogycan –Stain purple –Exotoxins (released when bacteria die) Gram- negative Gram-positive

E. coli E. coli is the lab rat of the bacterial world. E. coli is a normal resident of the large intestine in healthy people. It is a type of probiotic organism because it crowds out disease causing bacteria. E. coli also makes vitamin K which humans require to be healthy. Although it is generally a good microbe, some strains make people sick. The toxic strains of this microbe are responsible for about half of all cases of traveler's diarrhea. One famous strain, O157:H7, has caused disease in people who eat uncooked hamburger.

Antibiotics Antibiotics are drugs that combat bacteria by interfering with cellular functions –Penicillin – interferes with cell wall production –Tetracycline – interferes with protein production –Sulfa drugs – produced in the laboratory –Broad-spectrum antibiotics will affect a wide variety of organisms