title: House dust mites possess a polymorphic, single domain putative peptidoglycan d,l endopeptidase belonging to the NlpC/P60 Superfamily.
abstract: A 14 kDa protein homologous to the γ-d-glutamyl-l-diamino acid endopeptidase members of the NlpC/P60 Superfamily has been described in Dermatophagoides pteronyssinus and Dermatophagoides farinae but it is not clear whether other species produce homologues. Bioinformatics revealed homologous genes in other Sarcopteformes mite species (Psoroptes ovis and Blomia tropicalis) but not in Tetranychus urticae and Metaseiulus occidentalis. The degrees of identity (similarity) between the D. pteronyssinus mature protein and those from D. farinae, P. ovis and B. tropicalis were 82% (96%), 77% (93%) and 61% (82%), respectively. Phylogenetic studies showed the mite proteins were monophyletic and shared a common ancestor with both actinomycetes and ascomycetes. The gene encoding the D. pteronyssinus protein was polymorphic and intronless in contrast to that reported for D. farinae. Homology studies suggest that the mite, ascomycete and actinomycete proteins are involved in the catalysis of stem peptide attached to peptidoglycan. The finding of a gene encoding a P60 family member in the D. pteronyssinus genome together with the presence of a bacterial promotor suggests an evolutionary link to one or more prokaryotic endosymbionts.
authors.affiliation: Microbiology & Immunology, School of Pathology and Laboratory Medicine, The University of Western Australia, Crawley, WA, Australia.
authors.forename: Vivian H
authors.initials: VH
authors.lastname: Tang
authors.affiliation: Microbiology & Immunology, School of Pathology and Laboratory Medicine, The University of Western Australia, Crawley, WA, Australia.
authors.forename: Geoffrey A
authors.initials: GA
authors.lastname: Stewart
authors.affiliation: Microbiology & Immunology, School of Pathology and Laboratory Medicine, The University of Western Australia, Crawley, WA, Australia.
authors.forename: Barbara J
authors.initials: BJ
authors.lastname: Chang
keywords: BDGP, Berkeley Drosophila Genome Project; DAP, diaminopimelic acid; HDM, house dust mite; LytFM homologues; Mites; NNPP, Neural Network Promoter Prediction; NOD, nucleotide-binding oligomerisation domain-containing protein; NlpC/P60 Superfamily; Peptidoglycan; Structural modelling; gDNA, genomic DNA; pI, isoelectric points; γ-d-Glutamyl-l-diamino acid endopeptidase