In Verrucomicrobium spinosum and Chthoniobacter flavus, a four-gene operon that includes proteins with an N-terminal signal sequence for cleavage and methylation recurs many times. Each operon is likely to encode a membrane complex, the function of which is unknown. This model represents a long protein from this putative membrame complex, with members averaging about 1300 amino acids. The N-terminal region includes an apparent signal sequence. The function is unknown. Most cassettes are adjacent to an unusually large protein with both an outer membrane autotransporter region and PEP-CTERM putative protein-sorting motif. [Cell envelope, Surface structures]
Jiyao W et al.(2023). "The conserved domain database in 2023.",