Nitrate Reductase Gene Expression in Idiomarina Strain cos21 Obtained from Oxygen Minimum Zone of Arabian Sea
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This study analyses the induction and repression of nitrate reduction activity in a batch culture of Idiomarina strain cos21. On a change from aerobic to anaerobic respiration, the culture entered a stationary phase. The onset of this phase showed 3.75 fold increase in mRNA levels for the nitrate reductase enzyme. mRNA accumulated very rapidly during a short period, after which its overall concentration declined to reach a lower value. The level of nitrite reductase protein reached a maximum value at 36 h of growth when the oxygen concentration dropped below 10 µM. The data set provided here confer new insights into the understanding of the physiological response of Idiomarina strain cos21 to change in oxygen concentration allowing the bacterium to survive and adapt to a new environment by dissimilatory reduction of nitrate to nitrite, which serves to provide energy as the bacteria adapt to anaerobiosis. Main strategy used here is to induce, measure, and track the expression of microbial genes, while they grow in culture conditions to better mimic interaction in a natural environment. This study will help us with a better understanding of the nitrate reduction process in the oxygen minimum zone.
Authors thank the Director of the Institute for his help and encouragements. We are obliged for the support provided during the entire work by Head BOD Dr. Ramaiah. We thank Dr. Siby Kurian, Project leader of PSC0108 for all the support provided during work. Authors also thank Ram Murti Meena for helping with gene sequencing. Financial support from CSIR funds under PSC0108 is gratefully acknowledged. The NIO contribution number is 6304.
Funding was provided by National Institute of Oceanography, India.
Compliance with Ethical Standards
Conflict of interest
The authors declare that they have no conflict of interest with regard to this manuscript.
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