Effect of temperature on growth and chemotactic behaviour of Campylobacter jejuni.
OBJECTIVE
To determine the effect of two physiologically important temperatures on growth and chemotaxis in Campylobacter jejuni.


RESULTS
Growth curves of Camp. jejuni were compared at 37 degrees C and 42 degrees C. Chemotaxis was compared at 37 degrees C and 42 degrees C by the disc and capillary assays. Student's t-test was applied to the results of the capillary assay to assess the significance in the difference between chemotaxis at the two temperatures. Both, the growth rate and chemotactic ability of the isolate, were found to be greater at 37 degrees C.


CONCLUSIONS
Quorum sensing (related to population density), a regulation mechanism of virulence in micro-organisms, has been reported in Campylobacter. Chemotaxis is also a known virulence factor of Campylobacter. Both, growth (in terms of population density) and chemotaxis, being greater at 37 degrees C than at 42 degrees C, suggests that the physiological temperature of humans (37 degrees C) might be more favourable for the expression of virulence in Campylobacter than that of birds (42 degrees C).


CONCLUSIONS
It is as yet not known why Campylobacter causes disease in humans but is avirulent in birds. This study suggests that the human body temperature is optimum for growth and chemotaxis in Campylobacter. There is scope for the study of temperature regulation of other virulence determinants of Campylobacter.
Khanna
M R
MR
Department of Microbiology, University of Pune, Pune, India.
Bhavsar
S P
SP
Kapadnis
B P
BP
D000596:Amino Acids / Q000494:pharmacology; D000818:Animals; D001431:Bacteriological Techniques; D001647:Bile Acids and Salts / Q000494:pharmacology; D016123:Campylobacter jejuni / Q000187:drug effects / Q000254:growth & development* / Q000472:pathogenicity / Q000502:physiology*; D002196:Capillaries; D002241:Carbohydrates / Q000494:pharmacology; D002633:Chemotaxis / Q000187:drug effects; D003470:Culture Media / Q000737:chemistry; D006801:Humans; D013696:Temperature; D014774:Virulence
D000596:Amino Acids; D001647:Bile Acids and Salts; D002241:Carbohydrates; D003470:Culture Media