Roles for the two 1-butanol dehydrogenases of Pseudomonas butanovora in butane and 1-butanol metabolism.
Pseudomonas butanovora grown on butane or 1-butanol expresses two 1-butanol dehydrogenases, a quinoprotein (BOH) and a quinohemoprotein (BDH). BOH exhibited high affinity towards 1-butanol (K(m) = 1.7 +/- 0.2 microM). BOH also oxidized butyraldehyde and 2-butanol (K(m) = 369 +/- 85 microM and K(m) = 662 +/- 98 microM, respectively). The mRNA induction profiles of BOH and BDH at three different levels of 1-butanol, a nontoxic level (0.1 mM), a growth-supporting level (2 mM), and a toxic level (40 mM), were similar. When cells were grown in citrate-containing medium in the presence of different levels of 1-butanol, wild-type P. butanovora could tolerate higher levels of 1-butanol than the P. butanovora boh::tet strain and the P. butanovora bdh::kan strain. A model is proposed in which the electrons from 1-butanol oxidation follow a branched electron transport chain. BOH may be coupled to ubiquinone, with the electrons being transported to a cyanide-sensitive terminal oxidase. In contrast, electrons from BDH may be transferred to a terminal oxidase that is less sensitive to cyanide. The former pathway may function primarily in energy generation, while the latter may be more important in the detoxification of 1-butanol.
Vangnai
Alisa S
AS
Department of Biochemistry and Biophysics, Oregon State University, Corvallis, Oregon 97331-2902, USA.
Sayavedra-Soto
Luis A
LA
Arp
Daniel J
DJ
D020001:1-Butanol / Q000378:metabolism* / Q000633:toxicity; D000429:Alcohol Oxidoreductases / Q000235:genetics* / Q000378:metabolism*; D002073:Butanes / Q000378:metabolism* / Q000633:toxicity; D002455:Cell Division / Q000502:physiology; D004579:Electron Transport / Q000502:physiology; D015964:Gene Expression Regulation, Bacterial; D015971:Gene Expression Regulation, Enzymologic; D007700:Kinetics; D011549:Pseudomonas / Q000201:enzymology*; D012333:RNA, Messenger / Q000378:metabolism
D002073:Butanes; D012333:RNA, Messenger; C046888:butane; D020001:1-Butanol; D000429:Alcohol Oxidoreductases; C060833:butanol dehydrogenase