The MBOAT (membrane bound O-acyl transferase) family of
membrane proteins
Membrane proteins are common proteins that are part of, or interact with, biological membranes. Membrane proteins fall into several broad categories depending on their location. Integral membrane proteins are a permanent part of a cell membrane ...
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
Residue may refer to:
Chemistry and biology
* An amino acid, within a peptide chain
* Crop residue, materials left after agricultural processes
* Pesticide residue, refers to the pesticides that may remain on or in food after they are appli ...
and an
asparagine (Asn) or histidine within a more
hydrophilic region some 30-50 residues upstream.
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
Eukaryotes () are organisms whose cells have a nucleus. All animals, plants, fungi, and many unicellular organisms, are Eukaryotes. They belong to the group of organisms Eukaryota or Eukarya, which is one of the three domains of life. Bacte ...
.
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
Phospholipids, are a class of lipids whose molecule has a hydrophilic "head" containing a phosphate group and two hydrophobic "tails" derived from fatty acids, joined by an alcohol residue (usually a glycerol molecule). Marine phospholipids typ ...
re-modelling.
Structure
The structure for one MBOAT protein, DltB from ''
Streptococcus thermophilus'' (), 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. A computational model of human
ghrelin ''O''-acyltransferase (GOAT)Q96T53 revealed a transmembrane channel that facilitates octanoylation of the peptide hormone
ghrelin.
DltB and GOAT share structural similarities in their homologous regions, suggesting a common core fold for MBOAT family members.
Human proteins with this domain
References
*
{{InterPro content, IPR004299
Enzymes
Membrane proteins
Protein families