瘤胃真菌分离鉴定及酶学特性  被引量:3

Isolation,Identification and Enzymatic Characteristics of Rumen Fungi

在线阅读下载全文

作  者:王砀砀 赵聪聪 郭奇奇 刘丽慧[1] 张涛[1] 赵会会 曹阳春[1] 姚军虎[1] 

机构地区:[1]西北农林科技大学动物科技学院,杨凌712100

出  处:《农业生物技术学报》2017年第10期1668-1681,共14页Journal of Agricultural Biotechnology

基  金:国家自然基金(No.31472122和No.31402102);中国博士后科学基金(No.2015T81058和No.2014M552497);杨凌示范区产学研用协同创新重大项目(No.2016CXY-18)

摘  要:厌氧真菌(Neocallimastigomycota)具有很强的植物组织降解能力,是草食动物消化道内一类重要的降解植物细胞壁的功能菌。为筛选可提高粗饲料利用率的高植物细胞壁降解酶活性厌氧真菌,本研究采用亨盖特厌氧滚管技术从西农萨能奶山羊(Capra hircus)瘤胃中分离获得12株真菌菌株,通过形态学观察、核糖体内转录间隔区和28S rDNA D1/D2区基因序列分析确定其分类地位。测定12株真菌的植物细胞壁降解酶活性(木聚糖酶,羧甲基纤维素酶,微晶纤维素酶,乙酰酯酶和β-葡聚糖酶),并对活性最高菌株分泌的木聚糖酶和乙酰酯酶进行酶学特性分析。结果表明,12株厌氧真菌均鉴定为Piromyces属,分别命名为Piromyces sp.CN1~Piromyces sp.CN12,ITS基因序列Genbank登录号为KY368100~KY368111。其中,Piromyces sp.CN6的木聚糖酶、羧甲基纤维素酶和乙酰酯酶活性分别为1655.3、93.4和152.8 m U,显著高于其他菌株(P<0.05);Piromyces sp.CN3的微晶纤维素酶活性最高,但与Piromyces sp.CN6差异不显著(P>0.05);各菌株间β-葡聚糖酶活性差异不显著(P>0.05)。木聚糖酶与羧甲基纤维素酶、乙酰酯酶存在极显著正相关(P<0.01),与微晶纤维素酶呈显著正相关(P<0.05)。酶学特性表明,Piromyces sp.CN6分泌的木聚糖酶最适反应温度为50℃,最适pH为5.0,该酶在40℃和pH5.0~8.0下较稳定;K^+、Ca^(2+)和Co^(2+)对其有激活作用,Zn^(2+)、Cu^(2+)、Mg^(2+)、Fe^(2+)和Mn^(2+)抑制该酶活性。乙酰酯酶的最适反应温度为50℃,最适pH为9.0,该酶在40℃和pH 5.0~10.0下较稳定;Mg^(2+)、K+、Ca^(2+)对乙酰酯酶有激活作用,Zn^(2+)、Fe^(2+)、Co^(2+)和Mn^(2+)抑制该酶活性。本研究从奶山羊瘤胃内容物筛选获得的Piromyces sp.CN6具有较高的植物细胞壁降解酶活性,通过酶活测定和酶学特性分析,丰富和完善瘤胃真菌的酶系信息,为深入应用提供依据。Anaerobic fungi (Neocallimastigomycota) are important fiber- degrading functional microorganisms in the herbivores' digestive tract. The purpose of the present study was to isolate anaerobic rumen fungi with high activities of plant cell wall degrading enzymes for practical applications to improve the utilization of roughage. Twelve anaerobic fungi strains were isolated from the ruminal contents of Xinong Saanen dairy goat (Capra hircus) using the Hungate roll tube technique. The fungi strains were identified using the morphological characteristics, nucleotide sequence analysis of internal transcribed spacer region and 28S rDNA D1/D2 region. Meanwhile, activities of xylanase, carboxymethyl cellulase (CMCase), avicelase, acetyl esterase (AE) and β-glucanase of 12 fungi cultures were assayed, and the enzymatic characteristics of xylanase and AE produced by fungus with the highest enzyme activities were also analysed. The results showed that 12 anaerobic fungi strains belonged to Piromyces, named Piromyces sp. CNI- Piromyces sp. CN 12, respectively. The ITS gene Genbank number is KY368100-KY368111. The xylanase, CMCase and AE activities ofPiromyces sp. CN6 were 1655.3, 93.4 and 152.8 mU which were significantly higher than those of other fungi strains (P〈0.05). The avicelase activity of Piromyces sp. CN3 was the highest among these fungi, but its activity showed no difference with that of Piromyces sp. CN6 (P〉0.05). There was no significant difference on β-glucanase activity produced by fungi strains (P〉 0.05). The xylanase activities had extremely significant positive correlation with CMCase and AE activities (P〈0.01), and the xylanase activities had significant positive with avicelase activity (P〈0.05). The optimum temperature of CMCase activity was 50℃, and the optimum pH was 5.0. The CMCase was stable at 40 ℃ and pH 5.0-8.0. K+, Ca2+and Co2+ had active effects on its enzyme activity, whereas Zn2+, Cu2+, Mg2+, Fe2+ and Mn2+ had inhibitory be pr

关 键 词:瘤胃厌氧真菌 细胞壁降解酶 酶学特性 木聚糖酶 乙酰酯酶 

分 类 号:S827[农业科学—畜牧学] Q93[农业科学—畜牧兽医]

 

参考文献:

正在载入数据...

 

二级参考文献:

正在载入数据...

 

耦合文献:

正在载入数据...

 

引证文献:

正在载入数据...

 

二级引证文献:

正在载入数据...

 

同被引文献:

正在载入数据...

 

相关期刊文献:

正在载入数据...

相关的主题
相关的作者对象
相关的机构对象