Protein Family Models

This family contains haloacid dehalogenase-like hydrolase enzymes. (from Pfam)

Date:

2024-08-14

This family of proteins is a member of the IIIA subfamily of the haloacid dehalogenase (HAD) superfamily of hydrolases. All characterized members of this subfamily (TIGR01662) and most characterized members of the HAD superfamily are phosphatases. HAD superfamily phosphatases contain active site residues in several conserved catalytic motifs [1], all of which are found conserved here. One member of this family, the YrbI protein from H. influenzae has been cloned, expressed, purified and found to be an active 3-deoxy-D-manno-octulosonate 8-phosphate phosphatase[2]. Furthermore, its crystal structure has been determined [3]. This family consists of sequences from beta, gamma and epsilon proteobacteria, Aquifex, Fusobacterium, Porphyromonas and Methanosarcina. The Methanosarcina sequence is distinctive in that it is linked to an N-terminal cytidylyltransferase domain (PF02348) and is annotated as acylneuraminate cytidylyltransferase. This may give some clue as the function of these phosphatases. Several eukaryotic sequences scoring between trusted and noise are also closely related to this function such as the CMP-N-acetylneuraminic acid synthetase from mouse, but in these cases the phosphatase domain is clearly inactive as many of the active site residues are not conserved.

Date:

2021-04-27

This subfamily falls within the Haloacid Dehalogenase (HAD) superfamily of aspartate-nucleophile hydrolases. The Class III subfamilies are characterized by the lack of any domains located between either between the first and second conserved catalytic motifs (as in the Class I subfamilies, TIGR01493, TIGR01509, TIGR01488 and TIGR01494) or between the second and third conserved catalytic motifs (as in the Class II subfamilies, TIGR01460 and TIGR01484) of the superfamily domain. The IIIA subfamily contains five major clades: histidinol-phosphatase (TIGR01261, [3]) and histidinol-phosphatase-related protein (TIGR00213) which together form a subfamily (TIGR01656), DNA 3'-phosphatase (TIGR01663, TIGR01664), YqeG (TIGR01668) and YrbI (TIGR01670). In the case of histidinol phosphatase and PNK-3'-phosphatase, this model represents a domain of a bifunctional system. In the histidinol phosphatase HisB, a C-terminal domain is an imidazoleglycerol-phosphate dehydratase which catalyzes a related step in histidine biosynthesis. In PNK-3'-phosphatase, N- and C-terminal domains constitute the polynucleotide kinase and DNA-binding components of the enzyme.

Date:

2021-08-12

3-deoxy-manno-octulosonate-8-phosphatase KdsC is a HAD (haloacid dehalogenase) family hydrolase that catalyzes the hydrolysis of 3-deoxy-D-manno-octulosonate 8-phosphate (KDO 8-P) to 3-deoxy-D-manno-octulosonate (KDO) and inorganic phosphate

Date:

2018-07-25

Catalyzes hydrolysis of KDO 8-P to KDO and inorganic phosphate; functions in lipopolysaccharide biosynthesis

Gene:

kdsC

Date:

2021-09-22