台湾型传染性支气管炎病毒重组株的分离鉴定及S1基因序列和血清型分析  

Isolation and Identification of Taiwan Genotype Avian Infectious Bronchitis Virus Recombinant Strain and Analysis of Its S1 Gene Sequence and Serotype

作　　者：雍璐 吕迪 范文胜[1] 林丽婷 唐金文 张愉 林子学 韦平[1] 磨美兰[1] YONG Lu;Lü Di;FAN Wensheng;LIN Liting;TANG Jinwen;ZHANG Yu;LIN Zixue;WEI Ping;MO Meilan(College of Animal Science and Technology,Guangxi University,Nanning,Guangxi 530005)

机构地区：[1]广西大学动物科学技术学院,广西南宁530005

出　　处：《中国家禽》2022年第4期29-35,共7页China Poultry

基　　金：国家自然科学基金项目(31860715);广西重点研发计划(桂科AB21238003);广西科技重大专项(桂科AA17204057);广西自然科学基金项目(2018GXNSFAA281009、2019GXNSFAA245009、2020GXNSFDA297004)。

摘　　要：为了解传染性支气管炎病毒(IBV)在广西地区的遗传变异情况,研究对2020年广西某种鸡场疑似传染性支气管炎(IB)病鸡进行病原分离和鉴定,并对分离株进行S1基因序列同源性、系统进化树、糖基化位点、重组和血清型分析。结果显示:从发病鸡群中分离到一株IBV,该IBV分离株S1基因与常用疫苗株H120、4/91、LDT3-A以及QXL87的氨基酸相似性为76.0%~82.0%,且在氨基酸第17~20位之间缺失2个氨基酸,在第39~480位之间则存在11个氨基酸点突变;S蛋白裂解位点为RRFRR;分离株与参考株TW2575/98同属于Taiwan-Ⅰ亚型,与常用疫苗株亲源性较远。该分离株无潜在的O-糖基化位点,但含有18个潜在N-糖基化位点;与所有常用疫苗株相比,相同的N-糖基化位点只有1个,不同的有2个。重组分析表明该分离株来源于野毒株GX-NN130059(Taiwan-Ⅰ亚型,主亲本)与参考株SAIBK(CK/CH/LSC/99I型,次亲本)的重组。血清型分析表明分离株属于血清7型,与常用疫苗株及近年广西IBV流行株优势血清型均不相同。研究表明该株IBV来源于Taiwan-Ⅰ型病毒株重组,重组导致的变异以及血清型不同于常用疫苗株可能是造成该养殖场免疫失败的主要原因。研究首次从广西地方品种鸡分离到不同于常用疫苗株血清型的Taiwan-Ⅰ亚型IBV重组毒株,提示IB的防控仍然面临着严峻的挑战,有必要继续加强IBV的监控以及新型疫苗的研发。To understand the genetic variation of infectious bronchitis virus(IBV) in Guangxi, the pathogen was isolated and identified in infectious bronchitis(IB) suspected chickens of a breeding company in Guangxi in 2020. The S1 gene similarity, phylogenetic tree, potential glycosylation sites, recombination and serotype analysis of the isolate were carried out. The results showed that one IBV isolate was isolated and identificated from the disease chickens. The amino acids(aa) similarities between the IBV isolate and the vaccine strains H120, 4/91, LDT3-A and QXL87 were 76.0% to 82%. There were two amino acids deletions at 17 to 20 and 11 point mutations at 39 to 480 in the IBV isolate. The cleavage site within S protein of the isolate was RRFRR. The isolate and the reference strain TW2575/98 belonged to Taiwan-Ⅰ subtype, which was far phylogenetic relationship with the common vaccine strains. The isolate didn′t contain potential O-glycosylation sites, but had 18 potential N-glycosylation sites. Compared with all commonly used vaccine strains, only one N-glycosylation site was the same and two were different.The IBV isolate was a recombinant virus by GX-NN130059 isolate(Taiwan-Ⅰ type, the major parent) and reference strain SAIBK(CK/CH/LSC/99I type, the minor parent). Serotype identification showed that the isolate belonged to serotype 7, which was different from the common vaccine strains and the dominant serotype of IBV circulating strains in Guangxi in recent years. This study showed that the IBV strain was derived from the recombination of Taiwan-Ⅰ strains, and the mutation caused by recombination and the difference of serotype from commonly used vaccine strain might be the main reasons for the immunization failure in this farm. In this study, the recombinant strain of Taiwan-Ⅰ subtype IBV, which shared different serotypes from the common vaccine strains, was first isolated from the local breeds of chickens in Guangxi, suggesting that the prevention and control of IB still faces severe challenge. Therefore

关 键 词：鸡 IBV 分离鉴定 基因型 S1基因 重组 

分 类 号：S855.3[农业科学—临床兽医学]