Bacterial that synthesize a cell wall of peptidoglycan (murein) generally have several transglycosylases and transpeptidases for the task. This family consists of a particular bifunctional transglycosylase/transpeptidase in E. coli and other Proteobacteria, designated penicillin-binding protein 1B. [Cell envelope, Biosynthesis and degradation of murein sacculus and peptidoglycan]
Jiyao W et al.(2023). "The conserved domain database in 2023.",