Characterization of a Pseudomonas putida allylic alcohol dehydrogenase induced by growth on 2-methyl-3-buten-2-ol.
We have been working to develop an enzymatic assay for the alcohol 2-methyl-3-buten-2-ol (232-MB), which is produced and emitted by certain pines. To this end we have isolated the soil bacterium Pseudomonas putida MB-1, which uses 232-MB as a sole carbon source. Strain MB-1 contains inducible 3-methyl-2-buten-1-ol (321-MB) and 3-methyl-2-buten-1-al dehydrogenases, suggesting that 232-MB is metabolized by isomerization to 321-MB followed by oxidation. 321-MB dehydrogenase was purified to near-homogeneity and found to be a tetramer (151 kDa) with a subunit mass of 37,700 Da. It catalyzes NAD+-dependent, reversible oxidation of 321-MB to 3-methyl-2-buten-1-al. The optimum pH for the oxidation reaction was 10.0, while that for the reduction reaction was 5.4. 321-MB dehydrogenase oxidized a wide variety of aliphatic and aromatic alcohols but exhibited the highest catalytic specificity with allylic or benzylic substrates, including 321-MB, 3-chloro-2-buten-1-ol, and 3-aminobenzyl alcohol. The N-terminal sequence of the enzyme contained a region of 64% identity with the TOL plasmid-encoded benzyl alcohol dehydrogenase of P. putida. The latter enzyme and the chromosomally encoded benzyl alcohol dehydrogenase of Acinetobacter calcoaceticus were also found to catalyze 321-MB oxidation. These findings suggest that 321-MB dehydrogenase and other bacterial benzyl alcohol dehydrogenases are broad-specificity allylic and benzylic alcohol dehydrogenases that, in conjunction with a 232-MB isomerase, might be useful in an enzyme-linked assay for 232-MB.
Malone
V F
VF
Department of Chemistry and Biochemistry, and Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, Colorado 80309-0215, USA.
Chastain
A J
AJ
Ohlsson
J T
JT
Poneleit
L S
LS
Nemecek-Marshall
M
M
Fall
R
R
D000429:Alcohol Oxidoreductases / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D000595:Amino Acid Sequence; D004790:Enzyme Induction; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010084:Oxidation-Reduction; D000439:Pentanols / Q000378:metabolism*; D016958:Pseudomonas putida / Q000201:enzymology* / Q000254:growth & development / Q000302:isolation & purification; D012988:Soil Microbiology; D013379:Substrate Specificity
D000439:Pentanols; D000429:Alcohol Oxidoreductases; C027016:benzyl alcohol dehydrogenase; C027250:3-hydroxy-3-methylbutene