Ubiquitous bacteria from the genus Oleispira drive oil degradation in the largest environment
on Earth, the cold and deep sea. Here we report the genome sequence of Oleispira antarctica
and show that compared with Alcanivorax borkumensis—the paradigm of mesophilic
hydrocarbonoclastic bacteria—O. antarctica has a larger genome that has witnessed massive
gene-transfer events. We identify an array of alkane monooxygenases, osmoprotectants,
siderophores and micronutrient-scavenging pathways. We also show that at low temperatures,
the main protein-folding machine Cpn60 functions as a single heptameric barrel that
uses larger proteins as substrates compared with the classical double-barrel structure
observed at higher temperatures. With 11 protein crystal structures, we further report the
largest set of structures from one psychrotolerant organism. The most common structural
feature is an increased content of surface-exposed negatively charged residues compared to
their mesophilic counterparts. Our findings are relevant in the context of microbial
cold-adaptation mechanisms and the development of strategies for oil-spill mitigation in cold
M.K. and P.N.G. designed the work; T.N.C. performed physiological studies; M.K., M.F.,
Y.A.-R., A.B., N.L.-C., M.E.G., O.R.K., T.Y.N., S.K., I.L., O.V.G., M.M.Y. R.R. and P.N.G.
were associated with genome annotation; H.J.H. performed lipids and FAME analysis;
M.F., M-l.F., S.J., S.C. and J.P.A performed chaperonin anti-proteome analysis; A.-x. S.,
O.K., O.E., P.A.P., P.S. and Y.K. were associated with structural proteomics; A.T. and R.F.
were associated with functional proteomics; H.L. performed electron microscopy; R.D.
performed real-time PCR; M.M.-G. and M.F. performed DIGE proteome analysis;
M.G. was involved in siderophore production; O.N.R. performed genomic islands’
analysis; H.T. performed storage lipid compounds’ analysis; P.N.G. coordinated
Accession Codes: The genome sequence of Oleispira antarctica RB-8 has been deposited
in GenBank under accession core FO203512. Protein structures have deposited in PDB
under accession codes 3QVM (a/b hydrolase, OLEAN_C08020), 3QVQ (phosphodiesterase,
OLEAN_C20330), 3M16 (transaldolase, OLEAN_C18160), 3LQY (isochorismatase,
OLEAN_C07660), 3LNP (amidohydrolase, OLEAN_C13880), 3V77/3L53 (fumarylacetoacetate isomerase/hydrolase, OLEAN_C35840), 3VCR/3LAB
(2-keto-3-deoxy-6-phosphogluconate aldolase, OLEAN_C25130), 3IRU (phoshonoacetaldehyde
hydrolase, OLEAN_C33610), 3I4Q (inorganic pyrophosphatase,
OLEAN_C30460), 3LMB (protein with unknown function, OLEAN_C10530).