Hatakeyama K, Kohama K, Vertès A A, Kobayashi M, Kurusu Y, Yukawa H
Tsukuba Research Center, Mitsubishi Petrochemical Co., Ltd, Inashiki, Ibaraki, Japan.
DNA Seq. 1993;4(2):87-93. doi: 10.3109/10425179309020147.
The biotin biosynthetic pathway of three coryneform bacteria, Brevibacterium flavum, Brevibacterium lactofermentum, and Corynebacterium glutamicum were analysed by cross-feeding experiments using several Escherichia coli biotin-requiring mutants. The three strains of coryneform bacteria tested were able to convert 7-keto-8-aminopelargonic acid to biotin, through a biotin synthetic pathway identical to that from E. coli. The biotin biosynthetic gene, bioB, of B. flavum was cloned by phenotypic complementation of E. coli bioB mutants. The bioB gene was located on a 1.7 kb HindIII-SacI DNA fragment. Nucleotide sequence analysis of this fragment revealed that the bioB gene of B. flavum consists of a 1005 bp open reading frame. Its deduced amino acid sequence is 35.7% and 31.5% identical to that of the E. coli and Bacillus sphaericus bioB gene products, respectively. B. flavum mutants obtained by in vivo disruption of the bioB gene lost their ability to grow on minimal medium containing dethiobiotin, indicating that the bioB gene product is necessary for the conversion of dethiobiotin to biotin.
利用几种需要生物素的大肠杆菌突变体进行的交叉饲养实验，分析了三种棒状杆菌（黄色短杆菌、乳酸发酵短杆菌和谷氨酸棒杆菌）的生物素生物合成途径。所测试的三种棒状杆菌菌株能够通过与大肠杆菌相同的生物素合成途径，将7-酮-8-氨基壬酸转化为生物素。通过对大肠杆菌bioB突变体的表型互补，克隆了黄色短杆菌的生物素生物合成基因bioB。bioB基因位于一个1.7 kb的HindIII-SacI DNA片段上。对该片段的核苷酸序列分析表明，黄色短杆菌的bioB基因由一个1005 bp的开放阅读框组成。其推导的氨基酸序列分别与大肠杆菌和球形芽孢杆菌bioB基因产物的氨基酸序列具有35.7%和31.5%的同一性。通过体内破坏bioB基因获得的黄色短杆菌突变体失去了在含有脱硫生物素的基本培养基上生长的能力，这表明bioB基因产物对于将脱硫生物素转化为生物素是必需的。
