A new l haloacid dehalogenase from the Arctic psychrotrophic Pseudoalteromonas sp BSW20308

作者：Liao, Li^*; Sun, Xi; Zeng, Yinxin; Luo, Wei; Yu, Yong; Chen, Bo

来源：Polar Biology, 2015, 38(8): 1161-1169.

DOI：10.1007/s00300-015-1674-3

• L-Haloacid dehalogenase
• Pseudoalteromonas
• Arctic
• Psychrophile

Exploration of biological resources from the Arctic and the Antarctic attracts increasing attention worldwide. l-haloacid dehalogenases (l-HADs) are considered to have potential applications in bioremediation and synthetic chemistry. They were reported from terrestrial bacteria in nonpolar regions, but seldom from microorganisms inhabiting the Arctic Ocean or Antarctica. Here, we described a new l-HAD (HADII(BSW)) from psychrotrophic Pseudoalteromonas sp. BSW20308, isolated from the Arctic marine environment. HADII(BSW) was analyzed in silico, cloned, expressed and biochemically characterized. HADII(BSW) was evolutionarily distinct from previously characterized l-HADs, sharing only 34 % identity with l-HAD (DehRhb) from a Rhodobacteraceae family bacterium UDC319 as the closest relative. Although it was from a psychrotrophic bacterium, HADII(BSW) had an optimum temperature for activity of 40 A degrees C. However, it retained decent activity at low temperature, which is an advantage over previous l-HADs. It preferred short-chain substrates, with the maximum activity toward monobromoacetic acid (MBAA), followed by S-(-)-2-bromopropionic acid. HADII(BSW) had exceptionally low K-m (0.15 mM) and high V-max (13.22 mu mol/min/mg) with MBAA. The first investigation of an l-HAD from a psychrotrophic Pseudoalteromonas from the Arctic revealed its potential in industrial applications such as in synthetic chemistry and environmental protection. Hypotheses proposed in this study encouraged further research on its structure and catalytic mechanism, as well as its physiological role in situ.

• 出版日期2015-8
• 单位华东理工大学; 中国极地研究中心