Linnett P E, Tipper D J
J Bacteriol. 1976 Feb;125(2):565-74. doi: 10.1128/jb.125.2.565-574.1976.
Synthesis of enzymes functional in the synthesis of nucleotide precursors of peptidoglycan ceases upon initiation of sporulation in Bacillus sphaericus. During sporulation, two periods of synthesis of these enzymes occur. The first starts at spore septum formation and is conincident with forespore engulfment; it involves the synthesis of those enzymes required for making the precursor of vegetative-type peptidoglycan, including L-lysyl ligase but no mesodiaminopimelyl ligase. The second period occurs shortly before the appearance of cortex. It involves the synthesis of diaminopimelyl ligase and the other enzymes needed for making the precursor of cortical peptidoglycan, but not lysyl ligase. Both events are a consequence of derepression at the level of transcription. Neither period of synthesis occurs in asporogenous mutants whose morphological block is at the point of spore septum formation.
在球形芽孢杆菌中，肽聚糖核苷酸前体合成所需的功能性酶的合成在芽孢形成开始时停止。在芽孢形成过程中，这些酶会出现两个合成阶段。第一个阶段始于芽孢隔膜形成，并与前芽孢被吞噬同时发生；它涉及合成那些用于制造营养型肽聚糖前体所需的酶，包括L-赖氨酰连接酶，但不包括内消旋二氨基庚二酸连接酶。第二个阶段发生在皮层出现前不久。它涉及二氨基庚二酸连接酶和制造皮层肽聚糖前体所需的其他酶的合成，但不包括赖氨酰连接酶。这两个事件都是转录水平去阻遏的结果。在形态学阻断发生在芽孢隔膜形成点的无芽孢突变体中，这两个合成阶段都不会发生。
