Molecular Biotechnology, Institute of Biology, Leiden Universitygrid.5132.5, Leiden, The Netherlands.
mBio. 2022 Apr 26;13(2):e0045622. doi: 10.1128/mbio.00456-22. Epub 2022 Mar 31.
Peptidoglycan is a major constituent of the bacterial cell wall and an important determinant for providing protection to cells. In addition to peptidoglycan, many bacteria synthesize other glycans that become part of the cell wall. Streptomycetes grow apically, where they synthesize a glycan that is exposed at the outer surface, but how it gets there is unknown. Here, we show that deposition of the apical glycan at the cell surface of Streptomyces coelicolor depends on two key enzymes, the glucanase CslZ and the lytic polysaccharide monooxygenase LpmP. Activity of these enzymes allows localized remodeling and degradation of the peptidoglycan, and we propose that this facilitates passage of the glycan. The absence of both enzymes not only prevents morphological development but also sensitizes strains to lysozyme. Given that lytic polysaccharide monooxygenases are commonly found in microbes, this newly identified biological role in cell wall remodeling may be widespread. Lytic polysaccharide monooxygenases are used in industry for the efficient degradation of recalcitrant polysaccharide substrates. Only recently, we have begun to appreciate some of their important biological roles. In this article, we provide evidence that these enzymes are involved in remodeling peptidoglycan, which is a conserved component of the bacterial cell wall. Given that lytic polysaccharide monooxygenases are commonly found in microbes, this newly identified biological role in cell wall remodeling may be widespread.
肽聚糖是细菌细胞壁的主要成分，是为细胞提供保护的重要决定因素。除了肽聚糖，许多细菌还合成其他糖，这些糖成为细胞壁的一部分。链霉菌在顶端生长，在那里它们合成一种暴露在表面的聚糖，但它是如何到达那里的尚不清楚。在这里，我们表明，链霉菌细胞表面顶端聚糖的沉积依赖于两种关键酶，即葡聚糖酶 CslZ 和裂解多糖单加氧酶 LpmP。这些酶的活性允许局部重塑和肽聚糖的降解，我们提出这有助于糖的通过。这两种酶的缺失不仅阻止了形态发育，而且使菌株对溶菌酶敏感。鉴于裂解多糖单加氧酶在微生物中普遍存在，这种新发现的细胞壁重塑中的生物学作用可能很广泛。裂解多糖单加氧酶在工业中用于有效降解顽固的多糖底物。直到最近，我们才开始了解它们的一些重要生物学作用。在本文中，我们提供了证据表明，这些酶参与了肽聚糖的重塑，肽聚糖是细菌细胞壁的保守成分。鉴于裂解多糖单加氧酶在微生物中普遍存在，这种新发现的细胞壁重塑中的生物学作用可能很广泛。
