Rhamnosyltransferase involved in lipopolysaccharide biosynthesis. Bacterial outer membrane biogenesis; lipopolysaccharide biosynthesis. Belongs to the glycosyltransferase 2 family. PubMed:9097040, PubMed:9278503 and PubMed:16738553 sequences differ from that shown due to the presence of an IS5I insertion element between codons 148 and 149.