28. Swarming gives rise to a very thin film of bacteria on the agar surface, but swarming periods are interspersed with periods when the cells stop and undergo a cycle of growth and division so that the colony has a distinct zonation, clearly seen in Fig. A. Ability to degrade urea to ammonia, by production of the enzyme urease (Figure B)
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36. Morganella morganii panophthalmitis. The conjunctiva was haemorrhagic and necrotic with mucopurulent greenish pus discharge. The cornea was oedematous and opacified.
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39. Diseases caused by members of the Enterobacteriaceae Major pathogen Representative diseases Minor related genera Escherichia UTI, traveler’s diarrhea, diarrhea, neonatal meningitis Shigella Dysentery Salmonella Typhoid fever, enterocolitis Arizona, Citrobacter, Edwardsiella Klebsiella Pneumonia, UTI Enterobacter Pneumonia, UTI Serratia Pneumonia, UTI Proteus UTI Providencia, Morganella Yersinia Plague, enterocolitis, mesenteric adenitis
40. Gram-negative rods causing UTI or sepsis Species Lactose fermented Features of the organism Escherichia coli + Greenish metallic sheen on EMB Enterobacter cloacae + Usually nosocomial infections & often drug resistant Klebsiella pneumoniae + Large mucoid capsule and viscous colonies Serratia marcescens - Red pigment produced; nosocomial infections; drug resistant Proteus mirabilis - Swarming phenomenon; produce urease Pseudomonas aeruginosa - Blue-green pigment; fruity odor; nosocomial; drug resistant
41. Lactose fermentation by members of the Enterobacteriaceae & related organisms Lactose fermented rapidly Lactose fermented slowly Lactose not fermented E. coli: motile; flat, nonviscous colonies Edwardsiella, serratia, citrobacter, arizona, providencia, erwinia, vibrios Shigella sp.: non-motile; no gas from dextrose Enterobacter aerogenes: raised colonies; often motile; more viscous growth Salmonella sp.: motile, acid & usually gas from dextrose Klebsiella pneumoniae: very viscous, mucoid growth; non-motile Proteus sp.: swarming on agar; urea rapidly hydrolyzed Pseudomonas sp.: soluble pigments; sweetish smell
42. Triple sugar iron (TSI) agar reactions Reactions Representative Genera Slant Butt Gas H 2 S Acid Acid + - Escherichia, Enterobacter, Klebsiella Alkaline Acid - - Shigella, Serratia Alkaline Acid + + Salmonella, Proteus Alkaline Alkaline - - Pseudomonas
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