FabF Is Required for Piezoregulation of cis-Vaccenic Acid Levels and Piezophilic Growth of the Deep-Sea Bacterium Photobacterium profundum Strain SS9

AUTOR(ES)

Allen, Eric E.

FONTE

American Society for Microbiology

RESUMO

To more fully explore the role of unsaturated fatty acids in high-pressure, low-temperature growth, the fabF gene from the psychrotolerant, piezophilic deep-sea bacterium Photobacterium profundum strain SS9 was characterized and its role and regulation were examined. An SS9 strain harboring a disruption in the fabF gene (strain EA40) displayed growth impairment at elevated hydrostatic pressure concomitant with diminished cis-vaccenic acid (18:1) production. However, growth ability at elevated pressure could be restored to wild-type levels by the addition of exogenous 18:1 to the growth medium. Transcript analysis did not indicate that the SS9 fabF gene is transcriptionally regulated, suggesting that the elevated 18:1 levels produced in response to pressure increase result from posttranscriptional changes. Unlike many pressure-adapted bacterial species such as SS9, the mesophile Escherichia coli did not regulate its fatty acid composition in an adaptive manner in response to changes in hydrostatic pressure. Moreover, an E. coli fabF strain was as susceptible to elevated pressure as wild-type cells. It is proposed that the SS9 fabF product, β-ketoacyl–acyl carrier protein synthase II has evolved novel pressure-responsive characteristics which facilitate SS9 growth at high pressure.

Documentos Relacionados

• RNA Arbitrarily Primed PCR Survey of Genes Regulated by ToxR in the Deep-Sea Bacterium Photobacterium profundum Strain SS9
• Monounsaturated but Not Polyunsaturated Fatty Acids Are Required for Growth of the Deep-Sea Bacterium Photobacterium profundum SS9 at High Pressure and Low Temperature
• Use of a reporter gene to follow high-pressure signal transduction in the deep-sea bacterium Photobacterium sp. strain SS9.
• ompH gene expression is regulated by multiple environmental cues in addition to high pressure in the deep-sea bacterium Photobacterium species strain SS9.
• RecD Function Is Required for High-Pressure Growth of a Deep-Sea Bacterium