Characterization of the genes of the 2,3-butanediol operons from Klebsiella terrigena and Enterobacter aerogenes

Abstract

The genes involved in the 2,3-butanediol pathway coding for ct-acetolactate decarboxylase, a-acetolactate synthase (ae-ALS), and acetoin (diacetyl) reductase were isolated from Klebsiela terrigena and shown to be located in one operon. This operon was also shown to exist in Enterobacter aerogenes. The budAl gene, coding for ot-acetolactate decarboxylase, gives in both organisms a protein of 259 amino acids. The amino acid similarity between these proteins is 87%. The K. terrgena genes budB and budC, coding for at-ALS and acetoin reductase, respectively, were sequenced. The 559-amino-acid-long cx-ALS enzyme shows similarities to the large subunits of the Escherichia coli anabolic a-ALS enzymes encoded by the genes ilvB, ilvG, and ilvl. The K. terrigena a-ALS is also shown to complement an anabolic ce-ALS-deficient E. coli strain for valine synthesis. The 243-amino-acid-long acetoin reductase has the consensus amino acid sequence for the insect-type alcohol dehydrogenase/ribitol dehydrogenase family and has extensive similarities with the N-terminal and internal regions of three known dehydrogenases and one oxidoreductase.

Biochemical and transcription analysis of acetohydroxyacid synthase isoforms in Mycobacterium tuberculosis identifies these enzymes as potential targets for drug development

“…The increased expression of ilvG in in vitro aerated cultures as well as in the NRP-2 and extended NRP-2 (NRP-3) stages of hypoxia in the presence of acetate suggested that IlvG behaves as a catabolic AHAS. It was reported earlier that low oxygen levels and the presence of excess acetate activated the catabolic AHAS, leading to activation of the butanediol fermentation pathway (Blomqvist et al, 1993;Johansen et al, 1975;Mayer et al, 1995;Störmer, 1968a, b). The enhanced expression of ilvB2 and ilvG ex vivo and in acidic conditions also supports their role as catabolic AHASs.…”

“…and Leuconostoc sp.) and Bacillus subtilis (Blomqvist et al, 1993;Johansen et al, 1975;Mayer et al, 1995;Renna et al, 1993;Störmer, 1968b;Tsau et al, 1992); they are induced by conditions such as presence of an excess of acetate (Blomqvist et al, 1993;Johansen et al, 1975;Mayer et al, 1995;Störmer, 1968b;Störmer, 1977) and/or pyruvate (Tsau et al, 1992), by low external pH (5.5-6.5) and low oxygen levels, and during the stationary phase (Renna et al, 1993).…”

Characterization of a (2R,3R)-2,3-Butanediol Dehydrogenase as theSaccharomyces cerevisiae YAL060W Gene Product

“…Most prokaryotic 2,3-butanediol dehydrogenases characterized so far in terms of their stereospecificity toward the different 2,3-butanediol isomers and corresponding acetoins (such as the ones from Brevibacterium saccharolyticum, Klebsiella terrigena, and Klebsiella pneumoniae (47)(48)(49)) have characteristics of the SDR family of enzymes. Only one known example in prokaryotes, the BDH from P. putida, corresponds to an MDR enzyme (37).…”

“…Thus, as indicated in the multiple alignment of Fig. 1A, it 49 and Glu 68 , which are considered "second sphere ligands," interacting with the zinc ligands themselves). We believe that the third ligand of the catalytic zinc in BDH would be Glu 174 .…”

Characterization of partially purified alcohol dehydrogenase from Rhodococcus sp. strain GK1

“…A wide variety of bacteria (Seitz et al 1963 ;Ui et al 1987 ;Hummel et al 1989 ;Gibson et al 1991 ;Blomquist et al 1993) and yeasts (Louis-Eugène et al 1988 ;Verduyn et al 1988 ;Legeay et al 1989 ;Heidlas and Tressl 1990 ;Hang and Woodams 1993 ;Olguin-Castillo et al 1994) display a diacetyl reductase. Chicken liver has also been described as a source of this enzyme (Gibson et al 1991).…”