Proteins in this entry are identified as putative alpha-1,2-mannosidases based on the characterisation of the protein from Microbacterium sp. M-90 [1]. Most members of this family appear to have signal sequences and may, like the M-90 protein, be secreted. Some of the proteins from the dental pathogen Porphyromonas gingivalis have been described as immunoreactive with periodontitis patient serum.