Laboratoire de Pathologie Végétale, Institut National Agronomique Paris-Grignon, 16 rue Claude Bernard, 75231 Paris Cedex 05, France.
EMBO J. 1985 Mar;4(3):781-5. doi: 10.1002/j.1460-2075.1985.tb03697.x.
Erwinia chrysanthemi 3937 secretes four major pectate lyase isoenzymes (PL, EC 4.2.2.2) and one endocellulase (Cx, EC 3.2.1.4). A genomic library of this strain was constructed in the Lambda L47-1 vector, and screened for the presence of PL and Cx on pectate and caboxymethylcellulose agar. Among the seven Cx-positive phage clones, three were shown to encode an enzyme of the same mol. wt. as the one found in the culture supernatant of strain 3937. The 34 PL-positive phage clones were analyzed by electrofocusing and could, according to the PL they produced, be arranged in five classes. Phages from three classes produced three different single PL, named PLb, c and d. No common fragment was evidenced between the inserts of the phages of these three classes. This demonstrated that, in strain 3937, PLb, C, and d were encoded by three different genes called pelB, C, and D. Furthermore, our results suggest the existence of two additional genes encoding PLa and e. In addition, a pectin methylesterase gene was found closely linked to pelD.
菊欧文氏菌 3937 分泌四种主要的果胶裂解酶同工酶（PL，EC 4.2.2.2）和一种内切纤维素酶（Cx，EC 3.2.1.4）。该菌株的基因组文库构建在 Lambda L47-1 载体中，并在果胶和羧甲基纤维素琼脂上筛选 PL 和 Cx 的存在。在七个 Cx 阳性噬菌体克隆中，有三个被证明编码一种与 3937 菌株培养上清液中发现的同工酶相同分子量的酶。通过电聚焦分析 34 个 PL 阳性噬菌体克隆，并根据它们产生的 PL 将其排列在五个类别中。来自三个类别的噬菌体产生三种不同的单 PL，分别命名为 PLb、c 和 d。这三个类别的噬菌体插入物之间没有共同的片段。这表明，在菌株 3937 中，PLb、C 和 d 由三个不同的基因 pelB、C 和 D 编码。此外，我们的结果表明存在另外两个基因，分别编码 PLa 和 e。此外，还发现了一个与 pelD 紧密连锁的果胶甲酯酶基因。
