Examville.com - Bacterial Spores And Classification Of Bacteria

BACTERIAL SPORES Under conditions of limited supply of nutrition, certain bacteria form highly resistant, dehydrated forms called spores or endospores, capable of surviving under adverse conditions, e.g. (Bacillus species, Clostridium species, Gram-positive coccus sporosarcina) Features of bacterial spores  Are formed in response to certain adverse nutritional conditions  Are inactive bacterial cells  More resistant to desiccation, heat and various chemicals  Contain calcium dipicolinate which aids in heat resistance within the core  Germinate under favourable nutritional conditions  Helpful in identifying some species of bacteria  Spore germinate to produce a single vegetable cell

Classification of bacteria: Classification of bacteria is a mixture of easily determined practical characteristics (size, shape, colour, staining properties, respiration, reproduction) and of more sophisticated analysis of immunological and biochemical criteria. Diagnostic Genus Common species characteristics Gram-positive bacteria Cocci Staphylococcus Staph.aureus Streptococcus S. pyogenes S.pneumoniae Bacilli Aerobic Bacillus B. anthracis Mycobacterium M. tuberculosis Nocardia N. asteroides Anaerobic Clostridium CI. tetani Actinomyces A.israeli Facultative anaerobic Listeria L. monocytogenes Erysepelothrix E. rhusiopathiae Corynebacterium C. diphtheriae Gram-negative bacteria Cocci Neisseria N. meningitidis Bacilli Aerobic Pseudomonas P. aeruginosa Streptobacillus S. moniliformis Brucella B. abortus Bordetella B. pertussis Anaerobic Bacteroides B. fragilis Fusobacterium F. nucleatum Facultative Escherichia Esch. coli anaerobic Salmonella S. typhi Shigella Sh. flexneri Klebsiella K. pneumoniae Yersinia Y. pestis Campylobacter C. fetus Haemophilus H. influenzae Vibrio V. cholerae Spiral Treponema T. pallidum Borrelia B. recu"entis Leptospira L. icterohaemorrhagiae Other bacteria Wall deficient Obligate intracellular parasites

Mycoplasma

M. pneumoniae

Rickettsia Coxiella Chlamydia

R. prowazekii C. burnetti C. trachomatis