An evolutionarily conserved glycine-tyrosine motif forms a folding core in outer membrane proteins
Fig 2
(A) Alignments of the mortise-tenon regions in 8-stranded OMP β-barrels. There is 100% conservation of the glycine (dark blue, strand 6th) and very high conservation of the tyrosine (red, strand 5th) in the mortise-tenon motif. Alignments were prepared using PROMALS3D web server; the predicted β-strands are colored in blue, and the consensus secondary structure prediction is given below the alignment. OmpX—APC51088.1 Outer membrane protein X [Escherichia coli str. K-12 substr. W3110]; HypoProt_1—WP_039105847.1 hypothetical protein [Frischella perrara]; HypoProt_2—WP_044834085.1 hypothetical protein [Thalassomonas actiniarum]; OmpA—BAA35715.1 Outer membrane protein A [Escherichia coli str. K-12 substr. W3110]; OmpW—CDO14140.1 Outer membrane protein W [Klebsiella pneumoniae]; PagL_1—BAR70092.1 PagL [Pseudomonas aeruginosa]; PagL_2—AGW82166.1 PagL [Bordetella avium]; Ail—AAB36601.1 Ail [Yersinia pseudotuberculosis]; NspA—CAX50548.1 NspA [Neisseria meningitidis 8013]; OprF—AFM37279.1 OprF [Pseudomonas aeruginosa]; OmpP5—AAA03346.1 outer membrane protein P5 [Haemophilus influenzae]; MotB—WP_012154185.1 flagellar motor protein MotB [Shewanella pealeana]; OmpF—WP_013260126.1 Outer membrane porin F [gamma proteobacterium HdN1]; OmpA-Like—WP_011053841.1 OmpA-like protein [Buchnera aphidicola]; PagC—WP_067708083.1 PagC [Erwinia sp. ErVv1]; TailProt—CSH02213.1 Tail assembly protein [Shigella sonnei]; VirProt—WP_038626525.1 virulence protein [Pantoea sp. PSNIH2]; InvProt—SDG65145.1 attachment invasion locus protein [Vibrio xiamenensis]. (B) Structures of different 8-stranded β barrel proteins. The 5th and 6th β-strands are highlighted in yellow and the mortise-tenon motif is highlighted in blue and red accordingly. PDB codes: NspA [1P4T]; OmpA[1QJP]; OmpX[2MNH]; OprF[4RLC]; PagL[2ERV].