title: Anthranilate degradation by a cold-adapted Pseudomonas sp.
abstract: An alpine soil bacterium Pseudomonas sp. strain PAMC 25931 was characterized as eurypsychrophilic (both psychrophilic and mesotolerant) with a broad temperature range of 5-30 °C both for anthranilate (2-aminobenzoate) degradation and concomitant cell growth. Two degradative gene clusters (antABC and catBCA) were detected from a fosmid clone in the PAMC 25931 genomic library; each cluster was confirmed to be specifically induced by anthranilate. When expressed in Escherichia coli, the recombinant AntABC (anthranilate 1,2-dioxygenase, AntDO) converted anthranilate into catechol, exhibiting strict specificity toward anthranilate. Recombinant CatA (catechol 1,2-dioxygenase, C12O) from the organism was active over a broad temperature range (5-37 °C). However, CatA rapidly lost the enzyme activity when incubated at above 25 °C. For example, 1 h-preincubation at 37 °C resulted in 100% loss of enzyme activity, while a counterpart from mesophilic Pseudomonas putida mt-2 did not show any negative effect on the initial enzyme activity. These results suggest that CatA is a new cold-adapted thermolabile enzyme, which might be a product through the adaptation process of PAMC 25931 to naturally cold environments and contribute to its ability to grow on anthranilate there.
authors.affiliation: Division of Life Sciences, Korea Polar Research Institute, Incheon, Korea.
authors.forename: Dockyu
authors.initials: D
authors.lastname: Kim
authors.forename: Miyoun
authors.initials: M
authors.lastname: Yoo
authors.forename: Eungbin
authors.initials: E
authors.lastname: Kim
authors.forename: Soon Gyu
authors.initials: SG
authors.lastname: Hong
mesh_terms: D000222:Adaptation, Physiological; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D050548:Catechol 1,2-Dioxygenase / Q000235:genetics / Q000378:metabolism; D002396:Catechols / Q000378:metabolism; D003001:Cloning, Molecular; D003080:Cold Temperature; D004926:Escherichia coli / Q000235:genetics; D006899:Mixed Function Oxygenases / Q000235:genetics / Q000378:metabolism; D005810:Multigene Family; D016366:Open Reading Frames; D011549:Pseudomonas / Q000235:genetics / Q000254:growth & development / Q000302:isolation & purification / Q000378:metabolism*; D016958:Pseudomonas putida / Q000201:enzymology; D012988:Soil Microbiology; D013379:Substrate Specificity; D062367:ortho-Aminobenzoates / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D002396:Catechols; D062367:ortho-Aminobenzoates; D006899:Mixed Function Oxygenases; D050548:Catechol 1,2-Dioxygenase; C023440:anthranilate 2,3-dioxygenase(deaminating); C034221:catechol
keywords: Aromatic; Cold-adaptation; Degradation; Thermolabile enzyme