Bacteria account for 1000-fold more biomass than humans. They vary widely in shape and size. The morphological diversity of bacteria is due largely to the different peptidoglycan-based cell wall structures that encase bacterial cells. Although the basic structure of peptidoglycan is highly conserved, consisting of long glycan strands that are cross-linked by short peptide chains, the mature cell wall is chemically diverse. Peptidoglycan hydrolases and cell wall-tailoring enzymes that regulate glycan strand length, the degree of cross-linking, and the addition of other modifications to peptidoglycan are central in determining the final architecture of the bacterial cell wall. Historically, it has been difficult to biochemically characterize these enzymes that act on peptidoglycan because suitable peptidoglycan substrates were inaccessible. In this review, we discuss fundamental aspects of bacterial cell wall synthesis, describe the regulation and diverse biochemical and functional activities of peptidoglycan hydrolases, and highlight recently developed methods to make and label defined peptidoglycan substrates. We also review how access to these substrates has now enabled biochemical studies that deepen our understanding of how bacterial cell wall enzymes cooperate to build a mature cell wall. Such improved understanding is critical to the development of new antibiotics that disrupt cell wall biogenesis, a process essential to the survival of bacteria.

中文翻译：

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揭示细菌细胞壁水解酶和定制酶的活性，生物学作用和调控。

细菌占人类生物量的1000倍。它们的形状和大小差异很大。细菌的形态多样性很大程度上是由于包裹细菌细胞的基于肽聚糖的细胞壁结构不同所致。尽管肽聚糖的基本结构是高度保守的，它由通过短肽链交联的长聚糖链组成，但成熟的细胞壁在化学上是多样的。肽聚糖水解酶和调节聚糖链长度，交联度以及向肽聚糖添加其他修饰的细胞壁定制酶是决定细菌细胞壁最终结构的关键。从历史上看，很难对这些作用于肽聚糖的酶进行生物化学表征，因为无法获得合适的肽聚糖底物。在这篇综述中，我们讨论了细菌细胞壁合成的基本方面，描述了肽聚糖水解酶的调控以及多种生化和功能活性，并着重介绍了最近开发的制造和标记肽聚糖底物的方法。我们还回顾了现在如何利用这些底物进行生化研究，从而加深了我们对细菌细胞壁酶如何协同作用构建成熟细胞壁的理解。这种更好的理解对于开发破坏细胞壁生物发生的新抗生素至关重要，这是细菌存活所必需的过程。并重点介绍了最近开发的制造和标记确定的肽聚糖底物的方法。我们还回顾了现在如何利用这些底物进行生化研究，从而加深了我们对细菌细胞壁酶如何协同作用构建成熟细胞壁的理解。这种更好的理解对于开发破坏细胞壁生物发生的新抗生素至关重要，这是细菌存活所必需的过程。并重点介绍了最近开发的制造和标记确定的肽聚糖底物的方法。我们还回顾了现在如何利用这些底物进行生化研究，从而加深了我们对细菌细胞壁酶如何协同作用构建成熟细胞壁的理解。这种更好的理解对于破坏细胞壁生物发生的新抗生素的开发至关重要，这是细菌存活所必需的过程。