摘要
木聚糖酶是半纤维素酶系的重要组成部分,能够分解水稻、小麦等农作物秸秆中的半纤维素。研究探讨木聚糖酶相关基因及其功能,为进一步探讨木聚糖酶与草菇生物转化率之间的关系提供理论依据。首先通过生物信息学手段构建了草菇2个木聚糖酶基因xyn1和xynII编码氨基酸序列的系统进化树,然后从生物转化率不同的草菇菌株分别提取各自的RNA,反转录为cDNA后,采用实时荧光定量PCR技术分析了xyn1和xynII基因的转录表达情况;最后应用DNS法对这些菌株中的木聚糖酶活性进行了测定。研究结果表明,xyn1编码的氨基酸序列与草腐菌相似性较高,而xynII编码的氨基酸序列与木腐菌遗传差异较小。在木聚糖酶活性测定和实时荧光定量PCR结果中,不同菌株的木聚糖酶活性趋势与xynII的转录表达趋势相似,均呈现依次递减。草菇的木聚糖酶活性与其生物转化率之间存在正相关性,推测草菇不同菌株木聚糖酶活性差异可能表现在转录水平上的差异。
Xylanase plays an important role in degradation of hemicelluloses. This study aims at revealing the relationship between xylanase and Volvariella volvacea strains with different biological efficiency, and to understand which xyn genecontributes more to the biological efficiency of Volvariella volvacea. Xynl, Xynll and their homologous sequences were used to establish a phylogenetic tree. Relative gene expression from different strains was measured by using real-time PCR. The activity of xylanase in three V. volvacea strains with different biological efficiency was determined by the DNS method. The results showed that Xynl of V volvocea was closely related to that of straw-rot fungi, and Xynfl was closely related to that of wood-rot fungi. The xynll expression and xylanase activity in 0229 was significantly higher than that in Vbl or in A8 However, xynl expression in Vb2 was lower than that in 0229 or in Ag. Xylanase activities were significantly different among Volvariella volvacea strains 0229, Vbl and A8, indicating that xylanase activity may be positively correlated with biologica efficiency of Volvariella volvacea. The relative gene expression of xylanase was also different at transcriptional level, suggesting that xynll may be more important than xynl for the biological efficiency of Volvariella volvacea
出处
《菌物学报》
CAS
CSCD
北大核心
2014年第5期1074-1083,共10页
Mycosystema
基金
上海市科技兴农重点攻关项目(2011第1-2号)
上海市市级农口系统青年人才成长计划[沪农青字(2014)第1-17号]
