Characterisation of an L-haloacid dehalogenase from the marine psychrophile Psychromonas ingrahamii with potential industrial application.
The recombinant L-haloacid dehalogenase from the marine bacterium Psychromonas ingrahamii has been cloned and over-expressed in Escherichia coli. It shows activity towards monobromoacetic (100 %), monochloroacetic acid (62 %), S-chloropropionic acid (42 %), S-bromopropionic acid (31 %), dichloroacetic acid (28 %) and 2-chlorobutyric acid (10 %), respectively. The L-haloacid dehalogenase has highest activity towards substrates with shorter carbon chain lengths (≤ C3), without preference towards a chlorine or bromine at the α-carbon position. Despite being isolated from a psychrophilic bacterium, the enzyme has mesophilic properties with an optimal temperature for activity of 45 °C. It retains above 70 % of its activity after being incubated at 65 °C for 90 min before being assayed at 25 °C. The enzyme is relatively stable in organic solvents as demonstrated by activity and thermal shift analysis. The V max and K m were calculated to be 0.6 μM min(-1) mg(-1) and 1.36 mM with monobromoacetic acid, respectively. This solvent-resistant and stable L-haloacid dehalogenase from P. ingrahamii has potential to be used as a biocatalyst in industrial processes.
The Henry Wellcome Building for Biocatalysis, Biosciences, College of Life and Environmental Sciences, University of Exeter, Stocker Road, Exeter, EX4 4QD, UK.
Halina R
HR
Novak
Christopher
C
Sayer
Jana
J
Panning
Jennifer A
JA
Littlechild
D000085:Acetates / Q000378:metabolism; D000595:Amino Acid Sequence; D001483:Base Sequence; D055162:Biocatalysis; D003001:Cloning, Molecular; D019295:Computational Biology; D017931:DNA Primers / Q000235:genetics; D003999:Dichloroacetic Acid / Q000378:metabolism; D004926:Escherichia coli; D020563:Gammaproteobacteria / Q000201:enzymology*; D006867:Hydrolases / Q000235:genetics* / Q000378:metabolism*; D007218:Industrial Microbiology / Q000379:methods*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011422:Propionates / Q000378:metabolism; D011487:Protein Conformation; D017422:Sequence Analysis, DNA; D013696:Temperature
D000085:Acetates; D017931:DNA Primers; D011422:Propionates; C006972:chloroacetic acid; C016274:bromoacetate; D003999:Dichloroacetic Acid; D006867:Hydrolases; C034507:2-haloacid dehalogenase; C029658:propionic acid