SC6D7A.02c, hisE, phosphoribosyl-ATP pyrophosphatase, len: 90 aa; similar to SW:HIS2_SULSO (EMBL:U82227) Sulfolobus solfataricus phosphoribosyl-ATP pyrophosphatase HisE (EC 3.6.1.31), 94 aa; fasta scores: opt: 175 z-score: 245.2 E(): 4e-06; 33.3% identity in 90 aa overlap and to SW:HIS2_MYCTU (EMBL:Z97559) Mycobacterium tuberculosis phosphoribosyl-ATP pyrophosphatase HisE (EC 3.6.1.31), 93 aa; fasta scores: opt: 336 z-score: 452.1 E(): 1.2e-17; 60.0% identity in 90 aa overlap. Contains Pfam match to entry PF01503 PRA-PH, Phosphoribosyl-ATP pyrophosphohydrolase.

ATP phosphoribosyltransferase; Catalyzes the condensation of ATP and 5-phosphoribose 1- diphosphate to form N'-(5'-phosphoribosyl)-ATP (PR-ATP). Has a crucial role in the pathway because the rate of histidine biosynthesis seems to be controlled primarily by regulation of HisG enzymatic activity. Belongs to the ATP phosphoribosyltransferase family. Long subfamily.

SC4G6.21c, hisB, imidazoleglycerol-phosphate dehydratase, len: 197aa; previously sequenced therefore identical to SW:HIS7_STRCO. Contains Pfam match to entry PF00475 IGPD, Imidazoleglycerol-phosphate dehydratase and Prosite matches to PS00955 Imidazoleglycerol-phosphate dehydratase signature 2 and PS00954 Imidazoleglycerol-phosphate dehydratase signature 1.

Histidinol dehydrogenase; Catalyzes the sequential NAD-dependent oxidations of L- histidinol to L-histidinaldehyde and then to L-histidine.

Putative hisF, cyclase; IGPS catalyzes the conversion of PRFAR and glutamine to IGP, AICAR and glutamate. The HisF subunit catalyzes the cyclization activity that produces IGP and AICAR from PRFAR using the ammonia provided by the HisH subunit (By similarity).

hisH, amidotransferase; IGPS catalyzes the conversion of PRFAR and glutamine to IGP, AICAR and glutamate. The HisH subunit catalyzes the hydrolysis of glutamine to glutamate and ammonia as part of the synthesis of IGP and AICAR. The resulting ammonia molecule is channeled to the active site of HisF (By similarity).

SC4G6.22c, hisC1, histidinol-phosphate aminotransferase, len: 369aa; previously sequenced therefore identical to SW:HIS8_STRCO. Contains Pfam match to entry PF00222 aminotran_2, Aminotransferases class-II and Prosite match to PS00599 Aminotransferases class-II pyridoxal-phosphate attachment site.

Putative anthranilate synthase component I; Part of a heterotetrameric complex that catalyzes the two- step biosynthesis of anthranilate, an intermediate in the biosynthesis of L-tryptophan. In the first step, the glutamine-binding beta subunit (TrpG) of anthranilate synthase (AS) provides the glutamine amidotransferase activity which generates ammonia as a substrate that, along with chorismate, is used in the second step, catalyzed by the large alpha subunit of AS (TrpE) to produce anthranilate. In the absence of TrpG, TrpE can synthesize anthranilate directly from chorismate and high [...]

Tryptophan synthase alpha subunit; The alpha subunit is responsible for the aldol cleavage of indoleglycerol phosphate to indole and glyceraldehyde 3-phosphate. Belongs to the TrpA family.