Protein N-glycosylation in Archaea:: defining Haloferax volcanii genes involved in S-layer glycoprotein glycosylation
Protein N-glycosylation in Archaea:: defining Haloferax volcanii genes involved in S-layer glycoprotein glycosylation
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DOI：
10.1111/j.1365-2958.2006.05252.x
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发表时间：
2006-07-01
影响因子：
3.6
通讯作者：
Eichler, Jerry
中科院分区：
文献类型：
--
作者：
Abu-Qarn, Mehtap;Eichler, Jerry
在本研究中，对盐古菌 Haloferax volcanii 中的 N-糖基化过程进行了表征。最初，假定的 Hfx。通过生物信息学鉴定了参与真核或细菌 N-糖基化的基因的火山同源物。逆转录聚合酶链反应 (RT-PCR) 证实所提出的 N-糖基化基因已被转录，表明真正的蛋白质正在被编码。当检测到相关基因序列的家族时，显示了家族成员在各种生理和环境条件下的差异转录。基因删除表明某些基因（例如 alg11）是必需的，但也表明其他基因（例如 alg5 的两个版本）不是必需的。然而，删除 alg5-A 确实会导致生长减慢，并干扰表面 (S) 层糖蛋白糖基化，如通过 SDS-PAGE 上的迁移修改和糖染色方法检测到的。由于 stt3（古生菌中检测到的寡糖转移酶复合物的唯一成分）的缺失并不影响细胞活力，因此 N-糖基化似乎在 Hfx 中并不是必需的。火山。尽管如此，stt3 的缺失确实阻碍了细胞生长和 S 层糖蛋白糖基化。因此，推测与 Hfx 相关的基因。火山蛋白糖基化的鉴定以及解决所编码的多肽在修饰报告糖蛋白中所发挥的作用的能力，可以定义古菌N-糖基化途径的步骤。
In this study, characterization of the N-glycosylation process in the haloarchaea Haloferax volcanii was undertaken. Initially, putative Hfx. volcanii homologues of genes involved in eukaryal or bacterial N-glycosylation were identified by bioinformatics. Reverse transcription polymerase chain reaction (RT-PCR) confirmed that the proposed N-glycosylation genes are transcribed, indicative of true proteins being encoded. Where families of related gene sequences were detected, differential transcription of family members under a variety of physiological and environmental conditions was shown. Gene deletions point to certain genes, like alg11, as being essential yet revealed that others, such as the two versions of alg5, are not. Deletion of alg5-A did, however, lead to slower growth and interfered with surface (S)-layer glycoprotein glycosylation, as detected by modified migration on SDS-PAGE and glycostaining approaches. As deletion of stt3, the only component of the oligosaccharide transferase complex detected in Archaea, did not affect cell viability, it appears that N-glycosylation is not essential in Hfx. volcanii. Deletion of stt3 did, nonetheless, hinder both cell growth and S-layer glycoprotein glycosylation. Thus, with genes putatively involved in Hfx. volcanii protein glycosylation identified and the ability to address the roles played by the encoded polypeptides in modifying a reporter glycoprotein, the steps of the archaeal N-glycosylation pathway can be defined.