腐败希瓦氏菌适冷酶的低温应激表达与冷链流通中凡纳滨对虾腐败相关性研究

项目名称： 腐败希瓦氏菌适冷酶的低温应激表达与冷链流通中凡纳滨对虾腐败相关性研究

项目编号： No.31501551

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 食品科学、农学基础与作物学

项目作者： 钱韻芳

作者单位： 上海海洋大学

项目金额： 20万元

中文摘要： 冷链流通是保持生鲜水产品品质的重要手段，但仍有部分腐败微生物能适应低温环境并分泌适冷蛋白酶。腐败微生物酶解作用是导致水产品腐败变质的主要原因。目前，有关腐败微生物适冷酶的低温应激表达与水产品腐败相关性研究还未见报道。本项目以凡纳滨对虾典型腐败微生物腐败希瓦氏菌为研究对象，通过测定腐败希瓦氏菌在低温环境下的生长状况、酶活性及腐败产物含量来分析其冷适应特性和低温下的致腐败能力；应用蛋白质组学技术对比低温刺激下腐败希瓦氏菌差异蛋白的表达情况，并筛选出腐败希瓦氏菌产生的可能导致凡纳滨对虾腐败的主要适冷酶类；将腐败希瓦氏菌接种至无菌虾体上，运用反转录定量PCR法测定冷链流通中腐败希瓦氏菌分泌并与对虾腐败相关的适冷酶表达水平，分析其与对虾品质指标的相关性以确定导致对虾腐败的关键适冷酶。该项目的开展将有助于加深对低温环境下水产品腐败形成原因的了解，并为加强冷链流通在水产品品质控制方面的作用提供理论依据。

中文关键词： 腐败希瓦氏菌；适冷酶；凡纳滨对虾；腐败；冷链

英文摘要： Cold chain logistics is broadly applied to maintain the quality of aquatic products, although some kinds of microorganisms can still survive and grow in the low-temperature environment by producing a large amount of cold-adapted enzymes, which lead to the deterioration of aquatic products. However, little information about the effect of these cold-adapted enzymes from spoilage bacteria induced by low temperature on the spoilage of aquatic products has been reported yet. In this project, Shewanella putrefaciens isolated from Pacific white shrimp will be studied as a model. The growth curves, the activity of protease and the production of metabolites in vitro are going to be determined to evaluate the spoilage capacity of S. putrefaciens under low-temperature environments. The differential expression levels of extracellular enzymes will also be compared by proteome technology. The potential cold-adapted proteases of S. putrefaciens causing spoilage will be selected and their expression levels during the cold chain distribution process will be determined via Q-RT-PCR after the strain is inoculated into the shrimp, and their relationship with the changes of quality indicators of shrimp will be discussed. This study will improve the understanding about the spoilage process of aquatic foods under low temperature environments, and provide a proposal to improve the effectiveness of cold chain logistics on the quality control of aquatic products.

英文关键词： Shewanella putrefaciens;cold-adapted enzymes;Litopenaeus vannamei;spoilage;cold chain