Protein Family Models

This is a family of periplasmic proteins which are part of the transport system for alkylphosphonate uptake. (from Pfam)

Date:

2024-08-14

This family contains the NMT1 and THI5 proteins. These proteins are proposed to be required for the biosynthesis of the pyrimidine moiety of thiamine [1][2][3]. They are regulated by thiamine [2]. The protein adopts a fold related to the periplasmic binding protein (PBP) family. Both pyridoxal-5'-phosphate (PLP) and an iron atom are bound to the protein suggesting numerous residues of the active site necessary for HMP-P biosynthesis. The yeast protein is a dimer and, although exceptionally using PLP as a substrate, has notable similarities with enzymes dependent on this molecule as a cofactor [4]. [1]. 12271461. Functional analysis of yeast gene families involved in metabolism of vitamins B1 and B6. Rodriguez-Navarro S, Llorente B, Rodriguez-Manzaneque MT, Ramne A, Uber G, Marchesan D, Dujon B, Herrero E, Sunnerhagen P, Perez-Ortin JE;. Yeast. 2002;19:1261-1276. [2]. 2358444. nmt1 of fission yeast. A highly transcribed gene completely repressed by thiamine. Maundrell K;. J Biol Chem. 1990;265:10857-10864. [3]. 12777485. The THI5 gene family of Saccharomyces cerevisiae: distribution of homologues among the hemiascomycetes and functional redundancy in the aerobic biosynthesis of thiamin from pyridoxine. Wightman R, Meacock PA;. Microbiology. 2003;149:1447-1460. [4]. 23048037. The last piece in the vitamin B1 biosynthesis puzzle: structural and functional insight into yeast 4-amino-5-hydroxymethyl-2-methylpyrimidine phosphate (HMP-P) synthase. Coquille S, Roux C, Fitzpatrick TB, Thore S;. J Biol Chem. 2012;287:42333-42343. (from Pfam)

Date:

2024-10-16

Members of this family ABC transporter periplasmic binding proteins and represent one clade within a larger family that includes phosphate, phosphite, and phosphonate transporters. All members of the seed alignment occur near a gene for SelD, the selenium-activating protein needed to make selenocysteine or selenouridine. Context therefore suggests members should be able to transport selenate, although transporting other substrates as well (e.g. phosphonates) is possible. This model has no overlap with TIGR03431, whose members are found regularly with phosphonate catabolism operons.

Date:

2021-09-22

Phosphonates are a varied class of phosphorus-containing organic compound in which a direct C-P bond is found, rather than a C-O-P linkage of the phosphorus through an oxygen atom. They may be toxic but also may be used as sources of phosphorus and energy by various bacteria. Phosphonate utilization systems typically are encoded in 14 or more genes, including a three gene ABC transporter. This family includes the periplasmic binding protein component of ABC transporters for phosphonates [1] as well as other, related binding components for closely related substances such as phosphate [2] and phosphite [3]. A number of members of this family are found in genomic contexts with components of selenium metabolic processes suggestive of a role in selenate or other selenium-compound transport. A subset of this model in which nearly all members exhibit genomic context with elements of phosphonate metabolism, particularly the C-P lyase system (GenProp0232, [4]) has been built (TIGR03431) as an equivalog. Nevertheless, there are members of this subfamily (TIGR01098) which show up sporadically on a phylogenetic tree that also show phosphonate context and are most likely competent to transport phosphonates.

Gene:

phnD

Date:

2024-06-26