Microbial Biochemistry

10/6/08 11:08 AM Macromolecules -Proteins- structural- eg. Glycoproteins catalytic- eg. Enzymes -Carbohydrates- structural- eg. Glycoproteins, cellulose- energy -Lipids- structural, fats, storage -Nucleic Acids Proteins -primary-(aa), secondary (beta sheets and alpha helix), tertiary (s-s bonds and h-bonds) Quaternary (polypeptides) -Energy protease; enzymes exoenzymes and endoenzymes 1. casein proteins protein- casein protease 80% milk protein-exoenzyme short peptidases -coagulates with acid/heat casein peptidase energy for microbes Tests Caseing plate zone of proteolysis Collagen----gelatinase- exoenzymes ? digests connective tissue -collagen structural protein -gelatin h bonds -energy for microbe Test Gelatin tube solid <20 degrees c ; liquid> 25 degrees c +microbe - liquid<20c 3. coagulase -extracellular protein -staphylococcus ; Yasinapastis -exploits clothing system to evade immunesystem microbecoagulase +(staphylothrombin) prothrombin---thrombin (fibrinogen pr fibrin and clot formation) Carbohydrates -Mono (5 {ribose} galactose, fructose} -di- glycosidic bond- lactose glu + gal sucrose---glu +fru Polysacharide- cellulose, starch, chitin, glycogen Starch-amylase; amylopectin Amylase( maltose glucose ((GLUCASE)) or matltrioseglucose) Amylopectin (---alpha-dextrin(alpha dextrinase)glucose TEST Starch Plate nutrient agar + 0.4-0.5% starch. -add iodine (binds to starch) -Look for zone of clearance around colony Microbial Biochemistry 10/6/08 11:08 AM 10/6/08 11:08 AM