Members of this protein family are exclusive to the Bacteroidetes phylum (previously Cytophaga-Flavobacteria-Bacteroides). GldK is a lipoprotein linked to a type of rapid surface gliding motility found in certain Bacteroidetes, such as Flavobacterium johnsoniae. Knockouts of GldK abolish the gliding phenotype. GldK is homologous to GldJ. There is a GldK homolog in Cytophaga hutchinsonii and several other species that has a different, shorter architecture and is represented by a separate model. Gliding motility appears closely linked to chitin utilization in the model species Flavobacterium johnsoniae. Bacteroidetes with members of this protein family appear to have all of the genes associated with gliding motility.
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