Schwartz Arnold C, Gockel Gaby, Gross Julia, Moritz Bernd, Meyer Helmut E
Institut für Molekulare Physiologie und Biotechnologie der Pflanzen, Universität Bonn, Kirschallee 1, 53115 Bonn, Germany.
Arch Microbiol. 2004 Dec;182(6):458-66. doi: 10.1007/s00203-004-0730-0. Epub 2004 Oct 7.
faoA, the gene of the dye-linked NAD(P)-independent quinone-containing formaldehyde dehydrogenase of methylamine-grown Hyphomicrobium zavarzinii strain ZV 580 was sequenced and analyzed together with an apparent promoter region and adjoining genes in a 7.2-kb fragment of hyphomicrobial DNA. The formaldehyde dehydrogenase, identified as a periplasmic enzyme by its signal sequence, is distantly related to the soluble pyrroloquinoline-quinone-dependent glucose dehydrogenase of Acinetobacter calcoaceticus and to other predicted glucose dehydrogenase sequences. The promoter region, containing about 400 nucleotides upstream of faoA, comprised potential binding sites identical or highly similar to known consensus sequences of the sigma factors sigma(70) (housekeeping), sigma(H) (heat shock), sigma(F) (flagellar) and sigma(N) (nitrogen). The complex regulation of the transcription of faoA, which is suggested by this setting and emphasized by a possible heat-shock promoter, supports a hypothesis proposing an auxiliary role of the enzyme in lowering detrimental elevated concentrations of formaldehyde, which might arise in the course of stress or regulatory transitions disturbing balanced C(1) metabolism.
对甲基胺培养的扎瓦尔齐尼生丝微菌ZV 580菌株中与染料连接的不依赖NAD(P)的含醌甲醛脱氢酶的基因faoA进行了测序，并与丝状微生物DNA的一个7.2 kb片段中的一个明显启动子区域及相邻基因一起进行了分析。通过其信号序列鉴定为周质酶的甲醛脱氢酶，与乙酸钙不动杆菌的可溶性吡咯喹啉醌依赖性葡萄糖脱氢酶以及其他预测的葡萄糖脱氢酶序列有较远的亲缘关系。启动子区域在faoA上游约400个核苷酸处，包含与已知的σ因子σ(70)（管家）、σ(H)（热休克）、σ(F)（鞭毛）和σ(N)（氮）的共有序列相同或高度相似的潜在结合位点。这种情况表明且可能的热休克启动子进一步强调了faoA转录的复杂调控，这支持了一种假说，即该酶在降低应激或调节转变过程中可能出现的有害甲醛浓度升高方面具有辅助作用，这些应激或调节转变会扰乱平衡的C(1)代谢。
