Cold-Adapted β-Galactosidase from the Antarctic Psychrophile Pseudoalteromonas haloplanktis

Cold-adapted beta-galactosidase from the Antarctic psychrophile Pseudoalteromonas haloplanktis.

The beta-galactosidase from the Antarctic gram-negative bacterium Pseudoalteromonas haloplanktis TAE 79 was purified to homogeneity. The nucleotide sequence and the NH(2)-terminal amino acid sequence of the purified enzyme indicate that the beta-galactosidase subunit is composed of 1,038 amino acids with a calculated M(r) of 118,068. This beta-galactosidase shares structural properties with Esc...

Life in the Cold: Proteomics of the Antarctic Bacterium Pseudoalteromonas haloplanktis

A DNA ligase from the psychrophile Pseudoalteromonas haloplanktis gives insights into the adaptation of proteins to low temperatures.

The cloning, overexpression and characterization of a cold-adapted DNA ligase from the Antarctic sea water bacterium Pseudoalteromonas haloplanktis are described. Protein sequence analysis revealed that the cold-adapted Ph DNA ligase shows a significant level of sequence similarity to other NAD+-dependent DNA ligases and contains several previously described sequence motifs. Also, a decreased l...

A novel genetic system for recombinant protein secretion in the Antarctic Pseudoalteromonas haloplanktis TAC125

BACKGROUND The final aim of recombinant protein production is both to have a high specific production rate and a high product quality. It was already shown that using cold-adapted bacteria as host vectors, some "intractable" proteins can be efficiently produced at temperature as low as 4 degrees C. RESULTS A novel genetic system for the production and secretion of recombinant proteins in the ...

Antarctic marine bacterium Pseudoalteromonas sp. KNOUC808 as a source of cold-adapted lactose hydrolyzing enzyme

Psychrophilic bacteria, which grow on lactose as a carbon source, were isolated from Antarctic polar sea water. Among the psychrophilic bacteria isolated, strain KNOUC808 was able to grow on lactose at below 5°C, and showed 0.867 unit of o-nitrophenyl β-D-galactopyranoside(ONPG) hydrolyzing activity at 4°C. The isolate was gram-negative, rod, aerobic, catalase positive and oxidase positive. Opt...