Adaptations to high pressure of Nautilia sp. strain PV‐1, a piezophilic Campylobacterium (aka Epsilonproteobacterium) isolated from a deep‐sea hydrothermal vent

Abstract

Physiological and gene expression studies of deep‐sea bacteria under pressure conditions similar to those experienced in their natural habitat are critical for understanding growth kinetics and metabolic adaptations to in situ conditions. The Campylobacterium (aka Epsilonproteobacterium) Nautilia sp. strain PV‐1 was isolated from hydrothermal fluids released from an active deep‐sea hydrothermal vent at 9° N on the East Pacific Rise. Strain PV‐1 is a piezophilic, moderately thermophilic, chemolithoautotrophic anaerobe that conserves energy by coupling the oxidation of hydrogen to the reduction of nitrate or elemental sulfur. Using a high‐pressure–high temperature continuous culture system, we established that strain PV‐1 has the shortest generation time of all known piezophilic bacteria and we investigated its protein expression pattern in response to different hydrostatic pressure regimes. Proteogenomic analyses of strain PV‐1 grown at 20 and 5 MPa showed that pressure adaptation is not restricted to stress response or homeoviscous adaptation but extends to enzymes involved in central metabolic pathways. Protein synthesis, motility, transport, and energy metabolism are all affected by pressure, although to different extents. In strain PV‐1, low‐pressure conditions induce the synthesis of phage‐related proteins and an overexpression of enzymes involved in carbon fixation.

The Mystery of Piezophiles: Understudied Microorganisms from the Deep, Dark Subsurface

“…Interestingly, contradictory results were obtained from a study performed with Nautilia sp. PV-1 where a proteomics analysis showed a decrease in flagellin expression under high pressure [ 15 ].…”

“…The opposite results were found for Nautilia sp. PV-1, for which groEL was downregulated at a high hydrostatic pressure [ 15 ].…”

Life in Extreme Environments - Diversity, Adaptability and Valuable Resources of Bioactive Molecules

“…Enzymes extracted from piezophiles are resistant to high pressure and do not require any specialized modifications related to pressure. Enzymes isolated from piezophilic microbes have great potential in biotechnology (Table 1), especially in the food industry where high pressure is used to process and sterilize food [63]. Another enzymes chymotrypsin isolated from piezophilic microorganisms can function at high pressure and temperature and is used in many industrial processes [64].…”