1. Cytoplasmic (Cell) Membrane Located just inside the peptidoglycan layer. Phospholipid bilayer similar to eukaryotic membranes, but does not contain sterols (except Mycoplasma species). Functions: transport of molecules into cell energy generation by oxidative metabolism… Read More »Cytoplasmic (Cell) Membrane, Mesosome and Cytoplasm
like a stiff “canvas sack” around the bacterial cell. maintains cell structure. is a permeability barrier to large molecules (like lysozyme) and hydrophobic molecules; also provides protection from adverse environments like the GI tract. has… Read More »Outer Membrane of Gram-negative Cells
Structure Chemical Composition Function Essential Components Cell Wall Peptidoglycan Outer membrane of Gram- negative bacteria Surface fibers of Gram- positive bacteria Sugar backbone with peptide side chains… Read More »The Structure of Bacterial Cells
Name Reason Alternative Microscopic Approach Mycobacteria (Ex. M. tuberculosis) Too much lipid in cell wall so dye cannot penetrate Acid-fast stain Treponema pallidum Too thin to see Dark-field microscopy or fluorescent antibody Mycoplasma pneumoniae No… Read More »Medically important bacteria that cannot be seen in the Gram stain
It is difficult to classify all bacteria into clear-cut categories. Various classification methods are used, depending in part, on the purpose. Nomenclature Bacteria are given 2 names (usually Latin) denoting their genus and species… Read More »Classification of Bacteria
Property Prokaryotic Bacterial Cells Eukaryotic Human Cells DNA within a nuclear membrane No Yes Number of chromosomes 1 More than 1 Mechanism of Replication Binary Fission Mitosis Presence of organelles, e.g. Golgi, mitochondria, lysosomes,… Read More »Eukaryotes vs. Prokaryotes
Learning Objectives: You should be able to: describe the major differences between eukaryotic and prokaryotic cells and explain why it is important to know the differences. use bacterial nomenclature properly. describe the phenotypic features used… Read More »Bacterial Classification and Structure
The study and diagnosis of infectious diseases is approached from an organ system perspective. Upper and Lower Respiratory Tracts Gastrointestinal Tract Urinary Tract Genital Tract Central Nervous System Skin and Soft Tissues Eye Systemic and… Read More »Infective Syndromes
A. Observations of “acquired immunity” to diseases and primitive vaccination practices contributed to our understanding of the immune response to infectious agents and the design of passive and active immunization strategies. INTRODUCTION Routine immunization… Read More »Immunity and Immunization
Relative sizes of microorganisms: Protozoa > Red Blood cell > Yeast > Bacteria > Mycoplasma > Viruses Fungi 1. David Gruby (1841-1845) identified yeast infections as the cause of thrush and fungi as the cause… Read More »Other microorganisms as causative agents of disease