Fig. 4: Molecular determinants of relaxed acceptor-site specificity. | Nature Communications

Fig. 4: Molecular determinants of relaxed acceptor-site specificity.

From: Discovery of a single-subunit oligosaccharyltransferase that enables glycosylation of full-length IgG antibodies in bacteria

Fig. 4

a Electrostatic potential of various OST peptide-binding pockets modeled with either DQNAT (top) or QYNST (bottom) acceptor peptides (yellow). Electrostatic surfaces were generated based on calculations using the adaptive Poisson-Boltzmann solver (APBS)38. b Sequence alignments of conserved, short motifs in eukaryotic STT3s (human and plant STT3A and STT3B, protozoan Leishmania major STT3D and Trypanosoma brucei TbSTTA) and bacterial ssOSTs (ClPglB, CjPglB, DgPglB, DmPglB, DiPglB). Alignments shown were made using Clustal Omega web server multiple alignment editor64. Conserved residues are shaded gray while notable residues that deviate between eukaryotic and bacterial sequences are shaded yellow. c Structural model of QYNST peptide (yellow) in the peptide-binding pocket of the same OSTs in (a). Depicted in green are amino acids at the entrance to the peptide-binding cavity that cluster to create a positively charged patch in ClPglB but are neutral in all other OSTs. The SVXE/SVIE/TIXE motifs are depicted in gold.

Back to article page