來自內(nèi)蒙古農(nóng)業(yè)大學教育部乳品生物技術(shù)與工程重點實驗室，上海交通大學農(nóng)生學院的研究人員采用雙向凝膠電泳和質(zhì)譜分析技術(shù),，首次完成了干酪乳桿菌不同生長期蛋白表達參考圖譜，這一研究成果公布在在國際蛋白質(zhì)組學頂級雜志Molecular and Cellular Proteomics發(fā)表題目為“Proteomics Analysis of Lactobacillus casei Zhang,a New Probiotic Bacterium Isolated from Traditional Home-made Koumiss in Inner Mongolia of China.”的文章,。
干酪乳桿菌是眾多益生菌中重要的菌種之一,。研究組2002年從內(nèi)蒙古地區(qū)傳統(tǒng)發(fā)酵酸馬奶中自主分離,、篩選獲得1株性能優(yōu)異的益生菌-L.casei Zhang,，并對其益生特性進行了系統(tǒng)的研究,。2008年5月18日完成了該菌株全基因組序列測定染色體基因組（GenBank accession No:CP001084）和質(zhì)?；蚪Mplca36 （GenBank accession No:CP000935）序列測定和圖譜繪制,。
這篇文章是在傳統(tǒng)生理生化和基因組學研究基礎(chǔ)上對干酪乳桿菌進行的蛋白組學研究。研究采用雙向凝膠電泳和質(zhì)譜分析技術(shù),，首次完成了干酪乳桿菌不同生長期蛋白表達參考圖譜,，分別獲得了487±21（對數(shù)期）和494±13（穩(wěn)定期）個蛋白點；發(fā)現(xiàn)了47個蛋白點在對數(shù)期和穩(wěn)定期表現(xiàn)顯著的差異表達,。進一步分析顯示,，這些差異表達蛋白更多屬于脅迫應(yīng)答蛋白或細胞代謝中關(guān)鍵蛋白，推測它們在菌體生長和代謝,，尤其抵御和適應(yīng)乳酸或其它環(huán)境變化中起重要作用,。
蛋白質(zhì)組學研究對明確益生乳酸菌遺傳學背景，深入了解益生特性機理進而改造和選育優(yōu)良益生菌奠定了基礎(chǔ),，對提高我國益生乳酸菌研究的科技創(chuàng)新能力,、自主知識產(chǎn)權(quán)益生菌品牌打造和我國乳酸菌產(chǎn)業(yè)發(fā)展具有重要意義。（生物谷Bioon.com）
生物谷推薦原始出處：
Molecular and Cellular Proteomics 2009, 8: 2321-2338
Proteomic analysis of Lactobacillus casei Zhang, a new probiotic bacterium isolated from traditionally home-made Koumiss in Inner Mongolia of China
Rina Wu, Weiwei Wang, Dongliang Yu, Wenyi Zhang, Yan Li, Zhihong Sun, Junrui Wu, He Meng, and Heping Zhang
Lactobacillus casei Zhang, isolated from traditional home-made koumiss in Inner Mongolia of China, was considered as a new probiotic bacterium by probiotic selection tests. We carried out a proteomic study to identify and characterize proteins expressed by L. casei Zhang in the exponential phase and stationary phase. Cytosolic proteins of the strain cultivated in MRS broth were resolved by two-dimensional gel electrophoresis using pH 4-7 linear gradients. The number of protein spots quantified from the gels was 487±21 (exponential phase) and 494±13 (stationary phase) respectively, among which a total of 131 spots were identified by MALDI-TOF/MS and/or MALDI-TOF/TOF according to significant growth phase-related differences or high expression intensity proteins. Accompanied with analysis of the COG, CAI, GRAVY value of each protein identified to the whole set of genes encoding proteins of L. casei Zhang, the study provided a very first insight into the profile of protein expression as a reference map of L. casei. Forty-seven spots were also found in the study showed statistically significant differences between exponential phase and stationary phase. Thirty-three of them increased at least 2.5-fold in the stationary phase in comparison with the exponential phase, and including nineteen protein spots (e.g., Hsp20, Dnak, GroEL, LuxS, PK, GalU) whose intensity up-shifted above 3.0-fold. The transcriptional profiles were conducted to confirm several important differential expression proteins by using real-time PCR. The analysis suggests that the differentially expressed proteins were mainly categorized as stress response proteins and key components of central and intermediary metabolism, implicating these proteins might play potential important role for the adaptation to the surroundings, especially the accumulation of lactic acid in the course of growth, and the physiological processes in bacteria cell.
