Pyruvate relieves the necessity of high induction levels of catalase and enables Campylobacter jejuni to grow under fully aerobic conditions

Authors


Rab de Jonge, Laboratory for Zoonoses and Environmental Microbiology, RIVM, P.O. Box 1, 3720 BA Bilthoven, The Netherlands.
E-mail: rob.de.jonge@rivm.nl

Abstract

Aims:  Several cases of campylobacteriosis reported worldwide seemingly conflict with the strict growth requirements and sensitivity to environmental stress of Campylobacter jejuni. In this study, the need for a micro-aerobic environment [dissolved oxygen tension (DOT): 0·1–90%; 100% air saturation)] and the adaptive responses to oxygen stress were studied.

Methods and Results:  The growth of C. jejuni in continuous culture was assessed under different DOT in the presence or absence of pyruvate. In a medium without pyruvate, continuous cultures of C. jejuni showed typically micro-aerobic behaviour and cells were unable to grow under fully aerobic conditions. However in the presence of pyruvate (25 mmol l−1), continuous cultures of C. jejuni were able to grow in a broad DOT range, varying from 0·1% to at least 90%, and the catalase activity was decreased.

Conclusions:  Addition of pyruvate results in the decrease in the concentration of hydrogen peroxide, which enables C. jejuni to grow aerobically.

Significance and Impact of the Study:  New information on the oxidative physiology of C. jejuni and its ability to grow aerobically in media supplemented with pyruvate is presented.

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