The gene which codes for this protein in gut-bacteria is located in a novel putative operon for galactose metabolism. The protein appears to be a carbohydrate-processing phosphorolytic enzyme (EC:2.4.1.211), unlike either glycoside hydrolases or glycoside lyase. Intestinal colonisation by bifidobacteria is important for human health, especially in pediatrics, because colonisation seems to prevent infection by some pathogenic bacteria that cause diarrhoea or other illnesses. The operon seems to be involved in intestinal colonisation by bifidobacteria mediated by metabolism of mucin sugars. In addition, it may also resolve the question of the nature of the bifidus factor in human milk as the lacto-N-biose structure found in milk oligosaccharides.

1: Novel putative galactose operon involving lacto-N-biose phosphorylase in Bifidobacterium longum. Kitaoka M, Tian J, Nishimoto M; Appl Environ Microbiol. 2005;71:3158-3162. PMID:15933016