Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei 430072, People's Republic of China.
J Bacteriol. 2010 Apr;192(8):2239-45. doi: 10.1128/JB.01661-09. Epub 2010 Feb 5.
Inactivation of sll0861 in Synechocystis sp. strain PCC 6803 or the homologous gene alr2432 in Anabaena sp. strain PCC 7120 had no effect on the growth of these organisms at a light intensity of 30 micromol photons m(-2) s(-1) but reduced their growth at a light intensity of 5 or 10 micromol photons m(-2) s(-1). In Anabaena, inactivation of the gene also significantly reduced the rate of heterocyst differentiation under low-light conditions. The predicted products of sll0861 and alr2432 and homologs of these genes showed similarity to N-acetylmuramic acid 6-phosphate etherase (MurQ), an enzyme involved in peptidoglycan recycling, in Escherichia coli. E. coli murQ and the cyanobacterial homologs could functionally substitute for each other. We hypothesize that murQ in cyanobacteria promotes low-light adaptation through reutilization of peptidoglycan degradation products.
在 30 微摩尔光子 m(-2) s(-1)的光强下，Synechocystis sp. 菌株 PCC 6803 中的 sll0861 或 Anabaena sp. 菌株 PCC 7120 中的同源基因 alr2432 的失活对这些生物的生长没有影响，但在 5 或 10 微摩尔光子 m(-2) s(-1)的光强下，其生长受到抑制。在 Anabaena 中，基因的失活也显著降低了低光条件下异形胞分化的速度。sll0861 和 alr2432 的预测产物及其同源基因与大肠杆菌中的 N-乙酰胞壁酸 6-磷酸醚酶（MurQ），一种参与肽聚糖回收的酶，具有相似性。大肠杆菌 murQ 和蓝细菌同源物可以相互替代。我们假设蓝细菌中的 murQ 通过再利用肽聚糖降解产物来促进对低光的适应。
