Investigation on colanic acid and molecular detection of cytotoxic necrotizing factor in bacteria associated with post-operative wound infections

Abstract EN

A total of 60 samples from patients with postoperative wound infection were included in this study.

Only 50 (83 %) patients with positive bacterial culture and 10 (17 %) patients with negative culture.

Different types of bacteria were isolated from post-operative wound infections.

The predominant bacteria for gram negative was E.

coli.

In this study (13) isolates of E.

coli were identified (37.14 %) followed by (6) isolates of Proteus vulgaris (17.14 %), while (5) isolates of Enterobacter cloacae (14.28 %) were found, (4) isolate of both Klebsiella pneumoniae (11.42 %) and Pseudomonas aeruginosa (11.42 %) were found, (2) isolates Acinetobacter spp.

(5.7 %), and (1) isolated of Citrobacter spp.

(2.85 %) were isolated.

All isolates were subjected to produce colanic acid extracellularly.

It was found that colanic was produced at high level by Klebsiella pneumoniae (97 μg \ ml) ; followed by E.

coli (82 μg \ ml) and then Enterobacter cloacae (73 μg \ ml), whereas Acinetobacter and Citrobacter produced this acid sugar at low level (16 μg \ ml) and (4 μg \ ml) respectively, on contract to Proteus vulgaris which failed to produce it extracellularly.

Cytotoxic necrotizing facter-1 gene obtained from E.

coli was used as PCR marker for detection of CNF-1 in E.

coli and other gram negative bacteria which are isolated in the present study.

Besides, this factor was detected in whole DNA genome and also in DNA plasmid.

It was observed that amplicons were found in all bacterial DNA extracted from E.

coli, Klebsiella, Enterobacter and Proteus.

At the same time, amplicons were detected in plasmids extracted from Enterobacter and Proteus.