Hawtin R E, Arnold K, Ayres M D, Zanotto P M, Howard S C, Gooday G W, Chappell L H, Kitts P A, King L A, Possee R D
NERC Institute of Virology and Environmental Microbiology, Oxford, United Kingdom.
Virology. 1995 Oct 1;212(2):673-85. doi: 10.1006/viro.1995.1525.
A functional chitinase gene (chiA) has been identified in the genome of the Autographa californica nuclear polyhedrosis virus (AcMNPV). It is expressed in the late phase of virus replication in insect cells. High levels of both endo- and exochitinase activity were detected by 12 hr p.i. and remained stable throughout infection. An AcMNPV chiA protein-specific antibody was prepared using recombinant material prepared in bacteria. This was used to demonstrate that a product of approximately 58 kDa was synthesised in virus-infected cells. Immunofluorescence analysis of virus-infected cells showed that most chitinase was located in the cytoplasm. Primer extension analysis of mRNA from AcMNPV-infected cells confirmed that transcription initiated from a baculovirus late start site (TAAG), 14 nucleotides upstream from the putative translation initiation codon. The predicted protein sequence of the AcMNPV chiA shares extensive sequence similarity with chitinases from bacteria and, in particular, the Serratia marcescens chitinase A (60.5% identical residues). Phylogenetic analyses indicate that AcMNPV, or an ancestral baculovirus, acquired the chitinase gene from a bacterium via horizontal gene transfer.
在苜蓿银纹夜蛾核型多角体病毒（AcMNPV）的基因组中已鉴定出一个功能性几丁质酶基因（chiA）。它在昆虫细胞病毒复制的后期表达。感染后12小时检测到高水平的内切和外切几丁质酶活性，并且在整个感染过程中保持稳定。使用在细菌中制备的重组材料制备了AcMNPV chiA蛋白特异性抗体。这用于证明在病毒感染的细胞中合成了约58 kDa的产物。对病毒感染细胞的免疫荧光分析表明，大多数几丁质酶位于细胞质中。对来自AcMNPV感染细胞的mRNA进行引物延伸分析证实，转录从杆状病毒晚期起始位点（TAAG）开始，该位点位于假定的翻译起始密码子上游14个核苷酸处。AcMNPV chiA的预测蛋白质序列与来自细菌的几丁质酶具有广泛的序列相似性，特别是与粘质沙雷氏菌几丁质酶A（60.5％相同残基）。系统发育分析表明，AcMNPV或其祖先杆状病毒通过水平基因转移从细菌中获得了几丁质酶基因。
