Understanding plasmid effect on hyaluronic acid molecular weight produced by Streptococcus equi subsp zooepidemicus
Understanding plasmid effect on hyaluronic acid molecular weight produced by Streptococcus equi subsp zooepidemicus
复制标题
DOI：
10.1016/j.ymben.2009.09.001
复制
发表时间：
2010-01-01
影响因子：
8.4
通讯作者：
Nielsen, Lars K.
中科院分区：
文献类型：
--
作者：
Marcellin, Esteban;Chen, Wendy Y.;Nielsen, Lars K.
透明质酸是一种生物聚合物，在制药和化妆品行业具有重要的应用价值。用乳链菌肽诱导的空质粒对照转化的马链球菌亚种动物链球菌细胞显示出更高的分子量。这种分子量的增加与乳链菌肽启动子或抗生素抗性无关。使用2D DIGE，然后通过质谱，我们确定了UDP-N-乙酰葡糖胺生物合成（GlmU）的最后一步的上调和肽聚糖生物合成（MurA）的第一步的下调作为质粒效应的可能机制。过量表达GlmU以进一步增加活性对UDP-N-乙酰基-葡糖胺水平或分子量没有影响，而过量表达MurA降低UDP-N-乙酰基-葡糖胺水平和分子量。全球转录分析表明，GlmU和MurA活性的差异调节并没有反映在转录水平。这一结果表明，调控是在翻译或翻译后水平。两种clp蛋白酶的差异表达可以解释这种效应以及近300个基因转录水平的微小但显著的变化。(C)2009 Elsevier Inc. All rights reserved.
Hyaluronic acid is a biopolymer with valuable applications in the pharmaceutical and cosmetic industries. Streptococcus equi subspecies zooepidemicus cells transformed with a nisin-inducible, empty plasmid control displayed higher molecular weight. This increase in molecular weight is independent of the nisin promoter or antibiotic resistance. Using 2D DIGE followed by mass spectrometry, we identified up-regulation of the last step in UDP-N-acetyl-glucosamine biosynthesis (GlmU) and down-regulation of the first step in peptidoglycan biosynthesis (MurA) as possible mechanism for the plasmid effect. Over-expression of GlmU to further increase activity had no effect on UDP-N-acetyl-glucosamine levels or molecular weight, while over-expression of MurA reduced UDP-N-acetyl-glucosamine levels and molecular weight. Global transcriptional analysis revealed that differential regulation of GlmU and MurA activity was not reflected in transcription levels. This results, suggest that regulation is at a translational or post-translational level. Differential expression of two clp proteases may explain this effect as well as the small but significant changes in transcription levels of nearly 300 genes. (C) 2009 Elsevier Inc. All rights reserved.