C. Layers External to the Cell Wall Prokaryotes Prokaryotes have a variety of layers outside the cell wall Functions protection ingestion dehydration loss of nutrients attachment pathogenicity Form thick or thin, rigid or flexible layers depending upon composition Variable composition glycoproteins and polysaccharides – 1. Capsule Rigid tight matrix that excludes particles – protein or polysaccharide 2. Slime layer loosely bound layer easily deformed – 3. Extracellular Polymeric Substance (EPS) glycocalyx that helps cells bind to surfaces and other cells formation of biofilm – Glycocalyx term that collectively refers to both capsule and slime layer – 3. Surface layer (S-layer) nearly all bacteria and Archaea crystalline protein layer unknown function may function as permeability or protective barrier – D. Genetic Information Deoxyribonucleic acid (DNA) - macromolecule consisting of nucleotide monomers Backbone = 5'...-Phosphate-Sugar-Phosphate-Sugar -Phosphate-Sugar-…3' Nucleotide = nucleoside plus phosphate Nucleoside = deoxyribose + nitogenous base Purines adenine & guanine –
C. Layers External to the Cell Wall Prokaryotes Prokaryotes have a variety of layers outside the cell wall Functions protection ingestion dehydration loss of nutrients attachment pathogenicity Form thick or thin, rigid or flexible layers depending upon composition Variable composition – glycoproteins and polysaccharides 1. Capsule Rigid – tight matrix that excludes particles protein or polysaccharide 2. Slime layer loosely bound layer – easily deformed 3. Extracellular Polymeric Substance (EPS) glycocalyx that helps cells bind to surfaces and other cells – formation of biofilm Glycocalyx – term that collectively refers to both capsule and slime layer 3. Surface layer (S-layer) nearly all bacteria and Archaea crystalline protein layer unknown function – may function as permeability or protective barrier D. Genetic Information Deoxyribonucleic acid (DNA) - macromolecule consisting of nucleotide monomers Backbone = 5'...-Phosphate-Sugar-Phosphate-Sugar -Phosphate-Sugar-…3' Nucleotide = nucleoside plus phosphate Nucleoside = deoxyribose + nitogenous base Purines – adenine & guanine