Morphology & Identification Gram-negative non-spore forming rods. When motile, byperitrichous flagella. Primarily normal flora of gastrointestinal tract. E. coli>Klebsiella>Proteus>Enterobacter Free living, also transient colonizers of skin. Facultative anaerobes: mixed acid fermentation

Symbioses Commensalism: one partner benefits and the other is neither harmed nor benefited. Mutualism: both partners benefit. Parasitism: one partner benefits at the expense of the other

Bacterial genomics Organisation Linear chromosomes Borrelia burgdorferi Streptomyces coelicolor Multiple chromosomes Vibrio cholerae Plasmids Borrelia burgdorferi

The process of destroying all microbial forms. A sterile object is one free of all microbial forms, including bacterial spores

SIZE OF BACTERIA Unit for measurement : Micron or micrometer,μm: 1μm=10-3mm Size: Varies with kinds of bacteria, and also related to their age and external environment

General introduction Gram-negative, obligate intracellular coccobacilli bacteria that infect mammals and arthropods Rickettsiae are transmitted in the arthropods, which serves as both vector and reservior Both dna and rna Is sensitive to antibiotic

Spirochetes Gram negative Long, thin, helical, motile axial filaments locomotion between peptidoglycan layer/outer membrane runs parallel

Categories of Respiratory Viruses Orthomyxoviridae: Influenza virus Paramyxoviridae: Parainfluenza virus, Mumps virus; Measles, Respiratory syneytical virus Togaviridae: Rubella virus Coronaviridae: corona irus, sars virus Adenoviridae: human Adenovirus picornaviridae: Rhino virus;

球形,100-140nm,有包膜,包■通过血液途径、性 膜外有刺突 途径和垂直传播

Human cytomegalovirus Epstein-Barr- virus Herpes simplex virus Yellow fever virus Rubella