Chemotactic Behaviour of Campylobacter Strains as Function of Different Temperatures of 37 degree C and 42 degree C

The chemotactic behaviour of Campylobacter strains was determined in presence of different amino acids at two different temperatures of 37 degree C and 42 degree C. Two strains of Campylobacter, catalase positive (Campylobacter jejuni) and catalase negative (Campylobacter sputorum) were isolated from river water in Tonekabon, Iran and identified by phenotyping and 16srRNA gene sequencing methods. Chemotactic responses of the isolates were assessed towards a variety of amino acids viz., L-cystine, L-asparagine, L-histidine, L-aspartic acid, L-serine, L-phenylalanine, L-leucine and L-tryptophan by disc and capillary methods at two temperatures 37 degree C and 42 degree C. Campylobacter jejuni showed positive chemotactic response towards L-cystine, L-tryptophan, L-phenylalanine, L-leucine, L-asparagine and L-serine at both, 37 degree C and 42 degree C, however, it was greater at 37 degree C. Campylobacter sputorum showed negative or weak response towards all the amino acids. In addition, Campylobacter jejuni illustrated strong chemotactic response to L-asparagine followed by L-serine, and weak chemotaxis response to L-phenylalanine and L-cysteine at 37 degree C. Overall, Campylobacter jejuni showed relatively strong chemotactic response to some amino acids and its stimulation was greater at 37 degree C. Hence, the human body temperature (37 degree C) in comparison to avian body temperature (42 degree C) probably promotes chemotactic response of Campylobacter jejuni, which might be a reason for causing diseases in human beings compared to avian species.