title: Post-translational GPI lipid anchor modification of proteins in kingdoms of life: analysis of protein sequence data from complete genomes.
abstract: To investigate the occurrence of glycosylphosphatidylinositol (GPI) lipid anchor modification in various taxonomic ranges, potential substrate proteins have been searched for in completely sequenced genomes. We applied the big-pi predictor for the recognition of propeptide cleavage and anchor attachment sites with a new, generalized analytical form of the extreme-value distribution for evaluating false-positive prediction rates. (i) We find that GPI modification is present among lower and higher Eukaryota (approximately 0.5% of all proteins) but it seems absent in all eubacterial and three archaeobacterial species studied. Four other archaean genomes appear to encode such a fraction of substrate proteins (in the range of eukaryots) that they cannot be explained as false-positive predictions. This result supports the possible existence of GPI anchor modification in an archaean subgroup. (ii) The frequency of GPI-modified proteins on various chromosomes of a given eukaryotic species is different. (iii) Lists of potentially GPI-modified proteins in complete genomes with their predicted cleavage sites are available at http://mendel.imp.univie.ac.at/gpi/gpi_genomes.html. (iv) Orthologues of known transamidase subunits have been found only for EUKARYA: Inconsistencies in domain structure among homologues some of which may indicate sequencing errors are described. We present a refined model of the transamidase complex.
authors: Max-Delbrück-Centrum für Molekulare Medizin, Robert-Rössle-Strasse 10, D-13122 Berlin-Buch, Germany. birgit.eisenhaber@nt.imp.univie.ac.at
authors: B
authors: B
authors: Eisenhaber
authors: P
authors: P
authors: Bork
authors: F
authors: F
authors: Eisenhaber
mesh_terms: D001105:Archaea; D019843:Archaeal Proteins / Q000737:chemistry; D001419:Bacteria; D015815:Cell Adhesion Molecules / Q000737:chemistry; D005057:Eukaryotic Cells; D019143:Evolution, Molecular; D016678:Genome; D017261:Glycosylphosphatidylinositols / Q000145:classification* / Q000235:genetics*; D006801:Humans; D008433:Mathematics; D008562:Membrane Glycoproteins / Q000737:chemistry; D008969:Molecular Sequence Data; D009154:Mutation; D010802:Phylogeny; D020033:Protein Isoforms; D011498:Protein Precursors / Q000737:chemistry; D011499:Protein Processing, Post-Translational; D015800:Protozoan Proteins / Q000737:chemistry; D020539:Sequence Analysis, Protein / Q000379:methods; D000637:Transaminases / Q000737:chemistry
chemical_list: D019843:Archaeal Proteins; D015815:Cell Adhesion Molecules; C093316:GPAA1 protein, human; D017261:Glycosylphosphatidylinositols; D008562:Membrane Glycoproteins; C491190:PIGK protein, human; D020033:Protein Isoforms; D011498:Protein Precursors; D015800:Protozoan Proteins; D000637:Transaminases