State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.
University of Chinese Academy of Sciences, Beijing, China.
FEBS Lett. 2020 Feb;594(4):665-677. doi: 10.1002/1873-3468.13650. Epub 2019 Nov 19.
Adaptation to higher temperatures would increase the environmental competitiveness of psychrophiles, organisms that thrive in low-temperature environments. Methanolobus psychrophilus, a cold wetland methanogen, 'evolved' as a mesophile, growing optimally at 30 °C after subculturings, and cells grown with ample substrates exhibited higher integrity. Here, we investigated N-glycosylation of S-layer proteins, the major archaeal envelope component, with respect to mesophilic adaptation. Lectin affinity enriched a glycoprotein in cells grown at 30 °C under ample substrate availability, which was identified as the S-layer protein Mpsy_1486. Four N-glycosylation sites were identified on Mpsy_1486, which exhibited different glycosylation profiles, with N94 only found in cells cultured at 30 °C. An N-linked glycosylation inhibitor, tunicamycin, reduced glycosylation levels of Mpsy_1486 and growth at 30 °C, thus establishing a link between S-layer protein glycosylation and higher temperature adaptation of the psychrophilic archaeon M. psychrophilus.
适应更高的温度将提高嗜冷生物的环境竞争力，嗜冷生物是指在低温环境中茁壮成长的生物体。甲醇单胞菌（Methanolobus psychrophilus）是一种冷湿地甲烷菌，经过多次传代培养后，它“进化”成了一种中温生物，在 30°C 时生长最佳，而在有充足底物的情况下生长的细胞具有更高的完整性。在这里，我们研究了与中温适应相关的 S-层蛋白（主要的古菌包膜成分）的 N-糖基化。在有充足底物的情况下，在 30°C 下生长的细胞中，凝集素亲和作用富集了一种糖蛋白，该糖蛋白被鉴定为 S-层蛋白 Mpsy_1486。在 Mpsy_1486 上鉴定出了四个 N-糖基化位点，它们表现出不同的糖基化模式，只有 N94 存在于在 30°C 培养的细胞中。N-连接糖基化抑制剂，衣霉素，降低了 Mpsy_1486 的糖基化水平和在 30°C 下的生长，从而在嗜冷古菌 M. psychrophilus 的 S-层蛋白糖基化与较高温度适应之间建立了联系。
