MBOAT
Family of various acyltransferase enzymes
From Wikipedia, the free encyclopedia
The MBOAT (membrane bound O-acyl transferase) family of membrane proteins is a family of various acyltransferase enzymes. All family members contain multiple transmembrane domains and most carry two conserved residues, a conserved histidine (His) embedded in a hydrophobic stretch of residues and an asparagine (Asn) or histidine within a more hydrophilic region some 30-50 residues upstream.[1]
MBOAT enzymes catalyze the transfer of an acyl group from an acyl-coenzyme or accessory protein to one of several different substrates. The family is found from bacteria to eukaryotes.[2]
The family may be grouped into three categories, according to function:
- enzymes involved in neutral lipid biosynthesis;
- enzymes involved in protein/peptide acylation;
- enzymes involved in phospholipid re-modelling.[3]
Structure
The structure for one MBOAT protein, DltB from Streptococcus thermophilus (Q5M4V4), has been solved. DltB performs D-alanylation of cell-wall teichoic acid. It contains a ring of 11 transmembrane helices surrounding a tunnel that goes through the biological membrane. The tunnel connects to a partner, DltC, which carries the D-alanine to the conserved histidine residue of DltB MBOAT located at the bottom of the funnel.[4] A computational model of human ghrelin O-acyltransferase (GOAT) (Q96T53) revealed a transmembrane channel that facilitates octanoylation of the peptide hormone ghrelin.[5] DltB and GOAT share structural similarities in their homologous regions, suggesting a common core fold for MBOAT family members.