کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
2189139 1096199 2006 11 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Identification of Two Interaction Sites in SecY that Are Important for the Functional Interaction with SecA
موضوعات مرتبط
علوم زیستی و بیوفناوری بیوشیمی، ژنتیک و زیست شناسی مولکولی بیولوژی سلول
پیش نمایش صفحه اول مقاله
Identification of Two Interaction Sites in SecY that Are Important for the Functional Interaction with SecA
چکیده انگلیسی

The motor protein SecA drives the translocation of (pre-)proteins across the SecYEG channel in the bacterial cytoplasmic membrane by nucleotide-dependent cycles of conformational changes often referred to as membrane insertion/de-insertion. Despite structural data on SecA and an archaeal homolog of SecYEG, the identity of the sites of interaction between SecA and SecYEG are unknown. Here, we show that SecA can be cross-linked to several residues in cytoplasmic loop 5 (C5) of SecY, and that SecA directly interacts with a part of transmembrane segment 4 (TMS4) of SecY that is buried in the membrane region of SecYEG. Mutagenesis of either the conserved Arg357 in C5 or Glu176 in TMS4 interferes with the catalytic activity of SecA but not with binding of SecA to SecYEG. Our data explain how conformational changes in SecA could be directly coupled to the previously proposed opening mechanism of the SecYEG channel.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Molecular Biology - Volume 361, Issue 5, 1 September 2006, Pages 839–849
نویسندگان
, , , , , , ,