Med biochem - Exam 2 part 2 Questions And Answers All Correct

Med biochem - Exam 2 part 2 Questions And Answers All Correct Gram positive bacterial cell envelope - ANS-has OM, peptidoglycan layer, cytoplasmic membrane (IM), then the cytoplasm - Cytoplasmic membrane: phospholipids and protein - PG - Techoic Acid - S-Layer Proteins Gram stain of bacterial cell envelopes - ANS-Primary stain of crystal violet and a counterstain of safranin. differentiates gram negative (pink) and gram positive (purple) Functions of bacterial cell envelopes - ANS-1. acquisition of nutrients like AA, nucleotides, sugars, vitamins, and metals 2. Concentration of metabolites and enzymes 3. exclusion or export of noxious molecules: hydrophobic antibiotics, detergents Gram negative cell envelope - ANS-- OM: phospholipids, LPS, proteins - Periplasm: PG, binding proteins, enzymes - Inner membrane: phospholipids and proteins The structure of glucose (alpha and beta) Sucrose Lactose Maltose isomaltose cellobiose - ANS-Sucrose: alpha glucose and fructose Lactose: beta Galactose and glucose Maltose: Alpha glucose and glucose Isomaltose: Alpha glucose connected to carbon 6 of glucose Cellobiose: beta glucose and glucose Beta 1-4 linkages create strong or weak polymers? - ANS-Strong, cellulose, chitin and NAG/NAM of the PG later, H-bond Peptidoglycan cross linking - ANS-Peptidoglycan layer Linearly connected by beta 1-4 linkages between the sugars and alternating D and L AA in the pentapeptide to create a sturdy polymer, resistant to enzymatic degradation (look at slides for better reference) Parallel, planar network model for the bacterial cell to not burst Transpeptidation - ANS-Lys ε‐amino forms a peptide bond with the α‐carboxyl of the penultimate D‐Ala, releasing terminal D‐Ala penicillins and lysosome do what to the PG layer - ANS-the Transpeptidation reaction is inhibited by penicillins so it is not able to cross-link. discovered by alexander fleming. inhibits PG biosynthesis by CONTINUES...