1. صفات عمومي انتروباكترياسه ها
باسيل هاي گرم منفي مي باشند.
- اكسيداز آن ها منفي است.
- هوازي - بي هوازي اختياري مي باشند.
- گلوكز را تخمير مي كنند.
- قادر به احياي نيترات به نيتريت هستند.
- در انواع متحرك فلاژل از نوع پري تريش دارند.

2. باسیل های گرم منفی هوازی بیهوازی اختیاری
رشد در شرایط هوازی دربلاد ومک کانکی ↓
( + )
تست اکسیداز
( - )
TSIتخمیر گلوکز در
( + ) → ← ( - )
اسینتوباکتر Enterobacteriaceae

9. IMVIC

10. 11/27/2018
Dr.M.Sharifi

13. ONPG test

14. β- galactosidase & ONPG test
ο-Nitrophenyl-β-D-galactopyranoside is structurally similar to lactose : exception, glucose replaced by a ο-Nitrophenyl group
This test detects the enzyme β-galactosidase far more quickly than does the test for lactose fermentation
11/27/2018
Dr.M.Sharifi

15. ο-Nitrophenol is a chromophore : colorless when bounded , yellow in its free form
11/27/2018
Dr.M.Sharifi

16. ONPG test tablets that can be easily reconstituted by adding a small amount of water are available commercially and are convenient for use in the laboratory.
Organisms with strong β-galactosidase activity may produce a positive test within a few minutes after inoculation of the medium
11/27/2018
Dr.M.Sharifi

17. 11/27/2018
Dr.M.Sharifi

18. Escherichia coli (cont’d)
Characteristics
Dry, pink (lactose positive) colony with surrounding pink area on MacConkey

19. Escherichia coli (cont’d)
Ferments glucose, lactose, trehalose, & xylose
Positive indole and methyl red tests
Does NOT produce H2S or phenylalanine deaminase
Simmons citrate negative
Usually motile
Voges-Proskauer test negative

20. کلبسیلا تست های بیوشیمیایی
فلور طبیعی روده اما بیماریزا زمانی که به بافت های دیگر راه یابد
TSI A/A + gas
Urea +
Citrate +
MR-, VP+
Motility –
دارای هر دو آنتی ژن O و K

21. Klebsiella species (cont’d)
Significant biochemical reactions
Lactose positive
Most are urease positive
Non-motile

22. Klebsiella species Usually found in GI tract Four major species
K. pneumoniae is mostly commonly isolated species
Possesses a polysaccharide capsule, which protects against phagocytosis and antibiotics AND makes the colonies moist and mucoid
Has a distinctive “yeasty” odor
Frequent cause of nosocomial pneumonia

23. Enterobacter species
Comprised of 12 species; E. cloacae and E. aerogenes are most common
Isolated from wounds, urine, blood and CSF
Major characteristics
Colonies resemble Klebsiella
Motile
MR negative; VP positive

24. Enterobacter species (cont’d)

25. Enterobacter species
Comprised of 12 species; E. cloacae and E. aerogenes are most common
Isolated from wounds, urine, blood and CSF
Major characteristics
Colonies resemble Klebsiella
Motile
MR negative; VP positive

26. Serratia species (cont’d)
Major characteristics
Ferments lactose slowly
Produce characteristic pink pigment, especially when cultures are left at room temperature
S. marscens on
nutrient agar →

27. Hafnia species Hafnia alvei is only species
Has been isolated from many anatomical sites in humans and the environment
Occasionally isolated from stools
Delayed citrate reaction is major characteristic

28. Proteus, Morganella & Providencia species
All are normal intestinal flora
Opportunistic pathogens
Deaminate phenylalanine
All are lactose negative

29. Proteus species
P. mirabilis and P. vulgaris are widely recognized human pathogens
Isolated from urine, wounds, and ear and bacteremic infections
Both produce swarming colonies on non-selective media and have a distinctive “burned chocolate” odor
Both are strongly urease positive
Both are phenylalanine deaminase positive

30. Proteus species (cont’d)
A exhibits characteristic “swarming”
B shows urease positive on right

31. 11/27/2018
Dr.M.Sharifi

32. Morganella species Morganella morganii is only species
Documented cause of UTI
Isolated from other anatomical sites
Urease positive
Phenylalanine deaminase positive

33. Providencia species
Providencia rettgeri is pathogen of urinary tract and has caused nosocomial outbreaks
Providenicia stuartii can cause nosocomial outbreaks in burn units and has been isolated from urine
Both are phenylalanine deaminase positive

34. Citrobacter species
Citrobacter freundii associated with nosocomial infections (UTI, pneumonias, and intraabdominal abscesses)
Ferments lactose and hydrolyzes urea slowly
Resembles Salmonella sp.