Assembly of an oxalate decarboxylase produced under σK control into the Bacillus subtilis spore coat
Assembly of an oxalate decarboxylase produced under σK control into the Bacillus subtilis spore coat
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DOI：
10.1128/jb.186.5.1462-1474.2004
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发表时间：
2004-03-01
影响因子：
3.2
通讯作者：
Henriques, AO
中科院分区：
文献类型：
--
作者：
Costa, T;Steil, L;Henriques, AO
在枯草芽孢杆菌中，在孢子形成期间的不同时间合成超过30种多肽，并且它们在发育孢子的表面组装以形成称为外壳的多层蛋白质结构。被膜主要由三层组成，一层无定形的底层被膜，靠近下面的孢子皮层肽聚糖，一层层状内层，和一层电子致密的条纹状外层。B的乘积。枯草杆菌oxdD基因先前被证明当其在大肠杆菌中产生时具有草酸脱羧酶活性并且是孢子成分。在这项研究中，我们发现，OxdD特异性与孢子外壳结构，并在本文中，我们描述了其合成和组装的调节。我们发现oxdD的转录在孢子形成过程中作为一个单顺反子单位在sigma（K）的控制下被诱导，并受到GerE的负调控。我们还发现，本地化的功能OxdD-绿色荧光蛋白（GFP）在表面的发展孢子依赖于SafA形态发生蛋白，它定位在孢子皮层和涂层之间的界面。OxdD-GFP定位于cotE突变体中发育中的孢子周围，其不组装孢子外被层，但其不存在于由突变体产生的孢子中。总之，数据表明OxdD-GFP靶向于外套的内层。此外，我们发现oxdD的多拷贝等位基因的表达导致产生具有增加的OxdD水平的孢子，所述孢子能够降解草酸盐但对溶菌酶敏感。
Over 30 polypeptides are synthesized at various times during sporulation in Bacillus subtilis, and they are assembled at the surface of the developing spore to form a multilayer protein structure called the coat. The coat consists of three main layers, an amorphous undercoat close to the underlying spore cortex peptidoglycan, a lamellar inner layer, and an electron-dense striated outer layer. The product of the B. subtilis oxdD gene was previously shown to have oxalate decarboxylase activity when it was produced in Escherichia coli and to be a spore constituent. In this study, we found that OxdD specifically associates with the spore coat structure, and in this paper we describe regulation of its synthesis and assembly. We found that transcription of oxdD is induced during sporulation as a monocistronic unit under the control of sigma(K) and is negatively regulated by GerE. We also found that localization of a functional OxdD-green fluorescent protein (GFP) at the surface of the developing spore depends on the SafA morphogenetic protein, which localizes at the interface between the spore cortex and coat layers. OxdD-GFP localizes around the developing spore in a cotE mutant, which does not assemble the spore outer coat layer, but it does not persist in spores produced by the mutant. Together, the data suggest that OxdD-GFP is targeted to the interior layers of the coat. Additionally, we found that expression of a multicopy allele of oxdD resulted in production of spores with increased levels of OxdD that were able to degrade oxalate but were sensitive to lysozyme.