Positively and negatively charged residues have different effects on the position in the membrane of a model transmembrane helix

JOURNAL OF MOLECULAR BIOLOGY

卷:284

Article

Monné, M ; Nilsson, I ; Johansson, M ; Elmhed, N ; von Heijne, G

关键词: membrane protein;    protein structure;    glycosylation;    transmembrane helix;    charged residues;   

DOI  :  10.1006/jmbi.1998.2218

来源: Elsevier

【 摘 要 】

We have studied the effects of single charged residues on the position of a model transmembrane helix in the endoplasmic reticulum membrane using the glycosylation mapping technique. Asp and Glu residues cause a re-positioning of the C-terminal end of the transmembrane helix when placed in the one to two C-terminal turns but not when placed more centrally. Arg and Lys residues, in contrast, have little effect when placed in the two C-terminal turn but give rise to a more substantial shift in position when placed 9-11 residues from the helix end. We suggest that this difference between the effects of positively and negatively charged residues can be explained by the so-called snorkel effect, i.e. that the very long side-chains of Arg and Lys can reach up along the transmembrane helix to allow the terminal, charged moiety to reside in the lipid headgroup region while the C-alpha of the residue is positioned well below the membrane/water interface. (C) 1998 Academic Press.

【 授权许可】

Free