Spiess E, Sommer C, Görisch H
Institut für Biotechnologie, Fachgebiet Technische Biochemie, Technische Universität Berlin, Germany.
Appl Environ Microbiol. 1995 Nov;61(11):3884-8. doi: 10.1128/aem.61.11.3884-3888.1995.
Xanthobacter flavus 14p1 was isolated from sludge of the river Mulde by selective enrichment with 1,4-dichlorobenzene as the sole source of carbon and energy. The bacterium did not use other aromatic or chloroaromatic compounds as growth substrates. During growth on 1,4-dichlorobenzene, stoichiometric amounts of chloride ions were released. Degradation products of 1,4-dichlorobenzene were identified by gas chromatography-mass spectrometry analysis. 3,6-Dichloro-cis-1,2-dihydroxycyclohexa-3,5-diene and 3,6-dichlorocatechol were isolated from culture fluid. 2,5-Dichloromuconic acid and 2-chloromaleylacetic acid as well as the decarboxylation product 2-chloroacetoacrylic acid were identified after enzymatic conversion of 3,6-dichlorocatechol by cell extract. 1,4-Dichlorobenzene dioxygenase, dihydrodiol dehydrogenase, and catechol 1,2-dioxygenase activity were induced in cells grown on 1,4-dichlorobenzene. The results demonstrate that 1,4-dichlorobenzene degradation is initiated by dioxygenation and that ring opening proceeds via ortho cleavage.
黄杆菌属黄杆菌14p1是从穆尔德河的污泥中分离出来的，采用以1,4-二氯苯作为唯一碳源和能源进行选择性富集培养的方法。该细菌不利用其他芳香族或氯代芳香族化合物作为生长底物。在以1,4-二氯苯为底物生长过程中，会按化学计量释放出氯离子。通过气相色谱-质谱分析鉴定了1,4-二氯苯的降解产物。从培养液中分离出了3,6-二氯-顺式-1,2-二羟基环己-3,5-二烯和3,6-二氯儿茶酚。经细胞提取物对3,6-二氯儿茶酚进行酶促转化后，鉴定出了2,5-二氯粘康酸、2-氯马来酰乙酸以及脱羧产物2-氯乙酰丙烯酸。在以1,4-二氯苯为底物生长的细胞中诱导出了1,4-二氯苯双加氧酶、二氢二醇脱氢酶和儿茶酚1,2-双加氧酶的活性。结果表明，1,4-二氯苯的降解是通过双加氧作用起始的，且开环过程是通过邻位裂解进行的。
