Whole-genome sequencing of a psychrophilic bacterium, analysis of genes involved in cold adaptation, and exploitation of cold-active enzymes

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1. We carried out whole-genome analysis of Shewanella sp. Ac10, a psychrophile isolated from the Antarctic Ocean. The genome size was 4.5 Mbp, and the number of ORFs was about 4, 800.2. Shewanella sp. Ac10 grown at 4℃ produced a large quantity of a protein homologous to a cold-shock protein, CspA, from Escherichia coli.3. A collagenase of Shewanella sp. Ac1O was overproduced and characterized.4. We established a transformation method for Shewanella sp. Ac1O, isolated a promoter, and constructed an expression vector.5. A psychrotrophic bacterium, Acinetobacter sp. strain no. 6, was isolated from Siberian tundra soil. The bacterium produced extracellular lipolytic enzymes, and degraded various triglycerides in the medium at low temperatures. The bacterium is expected to be useful for the waste water treatment at low temperatures.6. The gene coding for a cold-active lipolytic enzyme with a substrate preference for fatty acid vinyl esters was cloned from Acinetobacter sp. strain no. 6. The enzyme was shown to be useful for the synthesis of esters by transesterification using vinyl esters as an acyl donor.7. We cloned the gene coding for a cold-active esterase from Acinetobacter sp. strain no. 6 that belongs to the EST group of the esterase/lipase family.8. We constructed a vector to introduce exogenous genes into Acinetobacter sp. strain no. 6 and isolated powerful promoters suitable for overexpression of exogenous genes.