Fatty acid adaptation in an Antarctic bacterium - Changes in primer utilization

The fatty acid composition and temperature/growth characteristics of a psychrophilic bacterium, strain ACAM 456, isolated from Antarctic sea-ice is reported. The bacterium produced acyl components that may be grouped in three different carbon chain types: even-chain, odd-chain and iso-branched odd-c...

Full description

Bibliographic Details
Published in:Microbiology
Main Authors: Nichols, DS, Russell, NJ
Format: Article in Journal/Newspaper
Language:English
Published: Soc General Microbiology 1996
Subjects:
Online Access:https://doi.org/10.1099/00221287-142-4-747
http://ecite.utas.edu.au/6730
Description
Summary:The fatty acid composition and temperature/growth characteristics of a psychrophilic bacterium, strain ACAM 456, isolated from Antarctic sea-ice is reported. The bacterium produced acyl components that may be grouped in three different carbon chain types: even-chain, odd-chain and iso-branched odd-chain. The proportions of these chain types varied according to growth temperature, and were manipulated by growth on L-serine, L-leucine or propionic acid as sole carbon sources, De novo fatty acid synthesis was investigated using sodium [1-14C]acetate, L-[U-14C]leucine and L-[U-14C]serine as radioactive precursors. Compared with a control culture, resuspension of mid-exponential phase cells in artificial seawater led to a change in the selection and/or intracellular availability of acyl chain primer molecules. The proportion of radiolabel incorporated into even-chain length components from cells declined, whereas the percentage of radiolabel present in odd-chain length components increased. An increase in incubation temperature augmented this effect, and also elicited a rise in the proportion of label present in branched-chain products. ACAM 456 manipulated the utilization of acyl chain primer molecules as an adaptive response to changes in environmental conditions. In particular, the regulation of odd-chain length fatty acids is described as a novel adaptational response.