Protein expression in the obligate hydrocarbon‐degrading psychrophile Oleispira antarctica RB‐8 during alkane degradation and cold tolerance

Abstract

Summary In cold marine environments, the obligate hydrocarbon‐degrading psychrophile Oleispira antarctica RB‐8, which utilizes aliphatic alkanes almost exclusively as substrates, dominates microbial communities following oil spills. In this study, LC–MS/MS shotgun proteomics was used to identify changes in the proteome induced during growth on n‐alkanes and in cold temperatures. Specifically, proteins with significantly higher relative abundance during growth on tetradecane (n‐C14) at 16°C and 4°C have been quantified. During growth on n‐C14, O. antarctica expressed a complete pathway for the terminal oxidation of n‐alkanes including two alkane monooxygenases, two alcohol dehydrogenases, two aldehyde dehydrogenases, a fatty‐acid‐CoA ligase, a fatty acid desaturase and associated oxidoreductases. Increased biosynthesis of these proteins ranged from 3‐ to 21‐fold compared with growth on a non‐hydrocarbon control. This study also highlights mechanisms O. antarctica may utilize to provide it with ecological competitiveness at low temperatures. This was evidenced by an increase in spectral counts for proteins involved in flagella structure/output to overcome higher viscosity, flagella rotation to accumulate cells and proline metabolism to counteract oxidative stress, during growth at 4°C compared with 16°C. Such species‐specific understanding of the physiology during hydrocarbon degradation can be important for parameterizing models that predict the fate of marine oil spills.

Comparative Proteomics of Marinobacter sp. TT1 Reveals Corexit Impacts on Hydrocarbon Metabolism, Chemotactic Motility, and Biofilm Formation

“…The n -hexadecane metabolism of Marinobacter sp. TT1 appears relatively analogous to the alkane metabolism of other marine alkane degraders [ 49 , 50 , 51 ], with our results suggesting important roles for the AupAB, AlkB2, and cytochrome P450 homologues and a number of involved dehydrogenases. The AupA homologue likely enables strain TT1 to take up n -hexadecane from the outer membrane, with the AupB homologue guiding the alkane to the inner membrane, where the terminal oxidation machinery is located [ 46 ].…”

Differential Expression and PAH Degradation: What Burkholderia vietnamiensis G4 Can Tell Us?

“…These genes belong to the dehydrogenase groups: Acyl-CoA dehydrogenase (Bcep1808_3337), aldehyde dehydrogenase (Bcep1808_6786), methylmalonate-semialdehyde dehydrogenase (Bcep1808_3335), and trifunctional transcriptional regulator/proline dehydrogenase/pyrroline-5-carboxylate dehydrogenase (Bcep1808_0122). Proline is directly related to the presence of a stressing agent, in the case of benzo(a)pyrene, and its high expression contributes to the resistance of the microorganism in the medium [ 61 ]. In a study conducted by O'Sullivan et al [ 18 ] with mutants for phenol degradation, genes such as aldehyde dehydrogenase were interrupted, which showed an effect on phenol degradation.…”

Marine Oil Snow, a Microbial Perspective

“…The type strain, Oleispira antarctica RB-8, is a psychrophilic alkane degrader with a broad growth optimum of 1-15 • C (Yakimov et al, 2003). It uses multiple mechanisms to compete at low temperatures, such as changes in the flagella structure/output to overcome increased viscosity, switching of flagella rotation to accumulate cells in an environment where it can outcompete other bacteria, and proline metabolism to counteract oxidative stress (Gregson et al, 2020). These psychrophilic adaptations of Oleispira most probably explain its absence from MOS generated from 25 • C surface water collected following the MC-252 spill (Arnosti et al, 2016).…”