权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Reinforcement of Silage-Making Lactobacilli and Their Utilization

青贮饲料乳酸菌的强化及其利用

基本信息

批准号：
07556094
负责人：
OGATA Seiya
金额：
$ 5.12万
依托单位：
KYUSHU UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (A)
财政年份：
1995
资助国家：
日本
起止时间：
1995 至 1997
项目状态：
已结题

项目摘要

Silage is a storable feed utilizing lactic fermentation. To develop a silage inoculant adaptable to the climatic conditions of south-west Japan such as Kyushu and Okinawa. we isolated many homofermentative lactobacilli strains with high lactic acid productivity under high temperature conditions. We then examined their properties and improved them to their greatest potential for use as silage inoculant.(1) The strains isolated were classified into L.plantaraum, L.pentosus, L.casei and L.rhamnosus by the usual methods and sequencing of partial 16S rRNA genes and phosphofructokinase genes and phosphofrutokinase gene pfk. A phagetying method was also effective for their easy and quick classification. : (2) 25% of 77 silage samples tested contained phages, most of which were infectious to L.plantaraum followed by L.casei. The phage contamination of silage resulted in the deterioration of quality. : (3) A phage resistant plasmid pLKS (2.1 kb) isolated was a rheta-replicating type. The phage resistant activity of pLKS might be due to the similarity between the replication factors of pLKS and phages. : (4) Lactobacillus-E.coli shuttle vector pUCLSEm was constructed by ligating pLKS to pUC119. : (5) A strain No. 161 belonging to Bacillus licheniformis, which had a high activity of nitrate reductase, was isolated from a compost. This train was tried to use for the elimination of NO^-_ in the silage. Furthermore, nitrate reductase gene narH with significant homology to the E.coli narH was cloned. : (6) The recombinant strains of L.plantaraum and L.casei were constructed with alpha-amylase gene, pfk and narH using vector pUCLSEm which had a phage resistant activity.

青贮饲料是一种利用乳酸发酵的可储存饲料。开发适应日本西南部九州、冲绳等地气候条件的青贮剂。我们在高温条件下分离到了许多高产乳酸的同质发酵乳酸杆菌菌株。然后，我们检查了它们的性能，并对它们进行了改进，使其成为青贮接种剂的最大潜力。(1)采用常规方法和部分16S rRNA基因、磷酸果糖激酶基因及磷酸果糖激酶基因pfk测序，将分离到的菌株分为植物l.s、戊糖l.s、干酪l.s和鼠李糖l.s。采用吞噬法对其分类简便、快捷。(2) 77份青贮饲料样品中噬菌体含量为25%，以植物乳杆菌为主，其次为干酪乳杆菌。青贮饲料中噬菌体的污染导致青贮饲料质量下降。(3)分离到的噬菌体抗性质粒pLKS （2.1 kb）为变异复制型。pLKS的抗噬菌体活性可能与pLKS的复制因子与噬菌体相似有关。(4)乳酸菌e。将pLKS连接到pUC119上构建大肠杆菌穿梭载体pUCLSEm。(5)从堆肥中分离到一株地衣芽孢杆菌161，该菌株具有较高的硝酸还原酶活性。该列车被用于消除青贮饲料中的NO^-_。并克隆出与大肠杆菌具有显著同源性的硝酸还原酶基因narH。(6)利用具有噬菌体抗性的pUCLSEm载体，构建了含有α -淀粉酶基因、pfk和narH的植物乳杆菌和干酪乳杆菌重组菌株。