Members of this protein family include the ygeW gene product of Escherichia coli. The function is unknown. Members show homology to ornithine carbamoyltransferase (TIGR00658) and aspartate carbamoyltransferase (carbamoyltransferase), and therefore may belong to the carbamoyltransferases in function. Members often are found in a large, conserved genomic region associated with selenium-dependent molybdenum hydroxylases.