Proteins with known a/b barrel structures

S.No	Name	code	Total
1	Flavocytochrome B2	1fcb	32
2	Glycholate oxidase	1gox	22
3	Trimethylamine dehydrogenase	2tmd	66
4	RUBISCO (large subunit)	1bur	33
5	mandelate racemase	1mns	19
6	muconate cyclo isomerase	1muc	29
7	a-amylase	1aqm	26
8	b-amylase	1bya	27
9	oligo 1-6 glucosidase	1uok	46
10	cyclodextrin glycosyl transferase	1ciu	35
11	pyruvate kinase	1pkl	21
12	xylose isomerase	1xya	31
13	N-5-phosphoryl anthranilate isomerase	1pii	28
14	indole-3 glycerol phosphate synthase	1a53	22
15	narbonin	1nar	21
16	fructose bis-phosphate aldolase	1a5c	15
17	2-dehydro-3-deoxy phospho gluonate aldolase	1kga
18	adenosine deaminase	1a4m	40
19	phosphotriesterase	1psc	21
20	1-3 b-glucanase	1ghs	11
21	1-3, 1-4 b glucanase	1aq0	6
22	endo-b-N-acetyl glucose aminidase	2ebn	10
23	urease (b subunit)	1fwj	29
24	old yellow enzyme	1oya	28
25	methylene tetrahydrofolate reductase	1b5t	12
26	inosine monophosphate dehydrogenase	1ak5	23
27	Transaldolase B	1onr	21
28	uroporphyrinogen decarboxylase	1uro	13
29	1,4 a D-glucan maltotetrahydrolase	2amg	37
30	2 phospho D-glycerate hydrolase	7enl	27
31	chloromuconate isomerase	2chr	22
32	endocellulase E1	1ece	21
33	Luciferase (flavin mono oxygenase)	1luc	13
34	Tryptophan synthase (a subunit)	2wsy	15
35	Triosephosphate Isomerase	1tpf	11
36	N-acetyl neuraminate lyase	1nal	4
37	aldose reductase	1ads	29
38	3-a-hydroxy steroid dehydrogenase	1afs	23
39	2-5-diketo D-gluconic acid reductase	1a80	24
40	quinolinate phosphoribosyl transferase	1qpo	18
41	aldehyde reductase	1cwn
42	dihydropteroate synthase	1aj0	17
43	b-glycosidase	1bgg	34
44	endo-b-1-4-xylanase	1bg4	17
45	Yeast Hypothetical protein	1b54	18
46	D-ribulose-5-phosphate 3-epimerase	1rpx	15
47	5-Amino laevulinate dehydrogenase	1aw5	14
48	methylmalonyl CoA mutase	4req	42
49	concanavalin B	1cnv	9
50	Hevamine	2hvm	8
51	Thimine phosphate synthase	2tps	11
52	D-glucarate dehydratase	1bqg	24
53	di hydro orotate dehydrogenase	2dor	9
54	Exo-1-4-b-D- glycanase	2exo	24
55	myrosinase (thioglucoside glucohydratase)	2myr	26
56	Alanine racemase	1bd0	25
57	isoamylase	1bf2	33
58	chitinase A	1ctn	32
59	phospholipase C (phosphoinositide-specific d 1)	1djz	24
60	phosphoenol pyruvate carboxylase	1fiy	57
61	Lux F gene product	1nfp	11
62	tRNA- Guanine transglycosylase	1pud	30
63	Pyruvate phosphate dikinase	2dik	78
64	ribonucleotide reductase R1 protein	6r1r	50
65	FR-1 protein (Fibroblast growth factor induced reductase protein)	1frb	22

Total No. of Salt Bridges : 1561 Arg-Asp= 428; Arg-Glu=394; His-Asp=110; His-Glu=95; Lys-Asp=281; Lys-Glu=253.

No.	Name	Pathway	Function
1	Flavocytochrome B2	Anaerobic Glycolysis	Mitochondrial enzyme , which oxidizes lactate to pyruvate
2	Glycholate oxidase	Photorespiration	Peroxisomal enzyme, oxidation of glycholate with simultaneous reduction of FMN, and reoxidation of FMN with O₂to liberate heat and H₂O₂.
3	Trimethylamine dehydrogenase		Trimethylamine + H₂O + acceptor = dimethylamine + formaldehyde + reduced acceptor.
4	RUBISCO (large subunit)	CO₂ Fixtaion Of Calvin Cycle	Stromal surface of the thylakoid membrane, catalyzes oxygenation rection to produce more glycholate molecules.
5	mandelate racemase	First Step In The Mandelate Pathway	Reducing enzyme which abstracts proton from the C atom adjacent to carboxylate to form an enolic intermediate. S-Mandelate = R-Mandelate
6	muconate cyclo isomerase	b-Keto Adipate Pathway	2,5, dihydro-5-oxofuran-2 Acetate = cis,cis, hexadienedioate.
7	a-amylase		Hydrolyzes amylopectin and amylose at internal a 1,4 linkages to yeild maltose, maltotriose and a dextrin.
8	b-amylase		Hydrolyzes starch to maltose by sequential removal of disaccharide units from the non reducing ends.
9	oligo 1-6 glucosidase		Hydrolysis of 1,6-a-Dglucosidic linkages in isomaltose and dextrins produced from starch and glycogen by a-amylase.
10	cyclodextrin glycosyl transferase		Maltose dependant enzyme which catalyzes the conversion of starch to cyclodextrin.
11	pyruvate kinase	Glycolysis	Conversion of Phosphoenolpyruvate to pyruvic acid by dephosphorylation reaction.
12	xylose isomerase	Glycolysis	Exhibits xylose isomerase activity over a wide range of temperatures from 60 to 100⁰C with an optimal enzyme activity at 85⁰C D-xylose = D-xylulose. Catalyzes interconversion between glucose and fructose.
13	N-5-phosphoryl anthranilate isomerase	Phenylalanine Biosynthesis.	N-5'-phosphoribosyl-anthranilate = 1-(2-carboxyphenylamino)-1-deoxy-D-ribulose 5-phosphate.
14	indole-3 glycerol phosphate synthase	Tryptophan Biosynthesis	1-(2-carboxyphenylamino)-1-deoxy-D-ribulose 5-phosphate = 1-indole-3-yl glycerol 3-phosphate + CO₂+H₂O
15	narbonin		Proposed that it has a chitinase activity but not confirmed. It is a storage protein.
16	fructose bis-phosphate aldolase	Glycolysis	Catalyzes the reversible cleavage of fructose 1,6 bisphosphate to dihydroxy acetone phosphate and glyceraldehyde 3 phosphate
17	2-dehydro-3-deoxy phospho gluonate aldolase	Purine Catabolic Pathway	2-dehydro-3-deoxy phospho gluonate = Pyruvate + D-Glyceraldehyde 3 phosphate
18	adenosine deaminase	Purine Catabolism	Adenosine + H₂O = Inosine + NH₃
19	phosphotriesterase		Pesticide detoxification Detoxofies organophosphate compounde by hydrolysis.
20	1-3 b-glucanase		Lysis of cellular walls containing b-1,3-glucans. Implicated in the defence against fungal pathogens. Hydrolysis of 1,3-b-D-glucosidic linkages in 1,3-b-D-glucans.
21	1-3, 1-4 b glucanase		Hydrolyses b-glucans containnig mixed b-1,3 and b-1,4 linkages. This enzyme is thermostable; its optimal temperature is near 65-70⁰C. Hydrolysis of 1,4-b-D-glycosidic linkages in b-D-glucans containing 1,3- and 1,4-bonds.
22	endo-b-N-acetyl glucose aminidase		An endoglycosidase that cleaves asparagine linked oligosaccharide after the first N acetyl glucoseamine residue.
23	urease (b subunit)		Hydrolysis of urea to ammonia. Urea + H₂O ® CO₂ + 2NH₃
24	old yellow enzyme		NADPH + Acceptor + NADP + Reduced Acceptor
25	methylene tetrahydrofolate reductase	Purine, Thymidylate, Methionine, Histidine, Formyl - Trna Biosnthesis.	5,10 - methylenetetrahydrofolate + NADP+ = 5,10 Methenyl tetrahydrofolate + NADPH 5,10 Methenyl tetrahydrofolate + NADPH + H₂O + Formyl Tetrahydrofolate
26	inosine monophosphate dehydrogenase	Denovo Guanine Nucleotide Synthesis.	Catalyzes the conversion of IMP to XMP
27	Transaldolase B	Link Between Pentosephosphate Pathway And Glycolysis.	Dihydroxy acetone moitey from a ketose donor to aldose acceptor. Sedoheptulose mono phosphate + 3 Glyceraldehyde 3 Phisphate = D Erythrose 4 Phosphate + D Fructose 6 Phosphate.
28	uroporphyrinogen decarboxylase	Porphyrin And Heme Biosynthesis.	Uroporphyrinogen III = coproporphyrinogen + 4 CO₂
29	1,4 a D-glucan maltotetrahydrolase	.	Catalyzes the liberation of maltose from 1,4-a-D- glucans. Stable at 80⁰ C, optimal activity at 75 degrees celsius.Hydrolysis of 1,4-a-glucosidic linkages in polysaccharides so as to remove successive maltose units from the non-reducing ends of the chains.
30	2 phospho D-glycerate hydrolase	Glycolysis	2-phospho-D-glycerate = phosphoenolpyruvate + H₂O
31	chloromuconate isomerase	3 Chlorocatechol Degradation	2-chloro-2,5-dihydro-5-oxofuran-2-acetate = 3-chloro-cis,cis-muconate (spontanous elimination of hcl produces cis-4-carboxymethylenebut-2-en-4-olide) (also reacts in reverse direction on 2-chloro-cis,cis-muconate).
32	endocellulase E1		Theromstable enzyme with an optimal temperature of 81 degrees celsius. Has a very high specific activity on carboxymethylcellulose. Endohydrolysis of 1,4-b-D-glucosidic linkages in cellulose.
33	Luciferase (flavin mono oxygenase)		Light-emitting reaction in luminous bacteria. FMNH₂ + RCHO + O₂ = FMN + RCOOH + H₂O + LIGHT.
34	Tryptophan synthase (a subunit)	Last (Fifth) Step In Biosynthesis Of Tryptophan.	The a subunit is responsible for the the aldol cleavage of indoleglycerol phosphate to indole and glyceraldehyde 3-phosphate.catalytic activityl-serine + 1-(indol-3-yl)glycerol 3-phosphate = l-tryptophan + glyceraldehyde 3-phosphate + H₂O
35	Triosephosphate Isomerase	Glycolysis	D-glyceraldehyde 3-phosphate = dihydroxy- acetone phosphate.
36	N-acetyl neuraminate lyase		N-acetylneuraminate = N-acetyl-D-mannosamine + pyruvate.
37	aldose reductase	Polyol Pathway	Catalyzes the NADPH-dependent reduction of a wide variety of carbonyl-containing compounds to their corresponding alcohols with a broad range of catalytic efficiencies. Alditol + NADP⁺ = aldose + NADPH+H⁺.
38	3-a-hydroxy steroid dehydrogenase		Besides being a 3-a-hydroxysteroid dehydrogenase, the enzyme can accomplish diverse functions: as quinone reductase, as an aromatic alcohol dehydrogenase, as dihydrodiol dehydrogenase, and as 9-, 11-, and 15-hydroxyprostaglandin dehydrogenase. Androsterone + NADP⁺ = 5-a-androstane-3,17-dione + NADPH+H⁺
39	2-5-diketo D-gluconic acid reductase	L-Ascorbic Acid (Vitamin C) synthesis.	2,5-diketo-D-gluconic acid + NADP+ = 2-keto-L-gluconic acid + NADPH+H⁺.
40	quinolinate phosphoribosyl transferase	Denovo NAD and NADP Synthesis	Nicotinate D-ribonucleotide + pyrophosphate + CO₂ = pyridine-2,3-dicarboxylate + 5-phospho-a-D-ribose 1-diphosphate.
41	aldehyde reductase		Alcohol + NADP⁺ = aldehyde + NADPH+H⁺
42	dihydropteroate synthase	Second Step In The Dihydrofolate Synthesis.	Dhps catalyzes the formation of the immediate precursor of folic acid. It is implicated in resistance to sulfonamide (by similarity). 2-amino-4-hydroxy-6-hydroxymethyl-7,8- dihydropteridine diphosphate + 4-aminobenzoate = pyrophosphate + dihydropteroate.
43	b-glucosidase	Cellulose Degradation	Hydrolysis of terminal, non-reducing b-D-glucose residues with release of b-D-glucose.
44	endo-b-1-4-xylanase	XYLAN Degradation	Endohydrolysis of 1,4-b-D-xylosidic linkages in xylans.
45	Yeast Hypothetical protein	not determined	not determined
46	D-ribulose-5-phosphate 3-epimerase	Calvin Cycle And Oxidative Pentose Phosphate Pathway	D-ribulose 5-phosphate = D-xylulose 5- phosphate.
47	5-Amino laevulinate dehydratase	Second Step In Porphyrin And Heme Biosynthesis.	2,5-aminolevulinate = porphobilinogen + 2 H₂O
48	methylmalonyl CoA mutase		Catalyzes the isomerization of succinyl-coa to methylmalonyl-coa during synthesis of propionate from tricarboxylic acid-cycle intermediates. This conversion most likely represents an important source of building blocks for polyketide antibiotic biosynthesis. It is unable to catalyze the conversion of isobutyryl-coa into n-butyryl-coa. R-2-methyl-3-oxopropanoyl-coa = succinyl-coa.
49	Concanavalin B	related to hevamine and chitinases. but no enzymatic activity.	May act as a carbohydrate-binding protein.
50	Hevamine		Bifunctional enzyme with lysozyme / chitinase activity. May have a role in plugging the latex vessel and cessation of latex flow. Hydrolysis of the b-1,4 linkages of N-acetyl-D-glucosamine polymers of chitin.hydrolysis of the 1,4-b-linkages between N-acetyl-D-glucosamine and n-acetylmuramic acid in peptidoglycan heteropolymers of the prokaryotes cell walls.
51	Thimine phosphate synthase	Last Step In The Thiamine ( TMP) Synthesis.	2-methyl-4-amino-5-hydroxymethylpyrimidine diphosphate + 4-4-methyl-5-(2-phosphonooxyethyl)-thiazole = pyrophosphate + thiamin monophosphate.
52	D-glucarate dehydratase		D-glucarate = 5-dehydro-4-deoxy-D-glucarate + H₂O
53	di hydro orotate dehydrogenase	Pyrimidine Biosynthesis.	L-dihydroorotate + O₂ = orotate + H₂O₂
54	Exo-1-4-b-D- glycanase		Hydrolyses both cellulose and xylan. Has also weak endoglucanase activity. The biological conversion of cellulose to glucose generally requires three types of hydrolytic enzymes: (1) endoglucanases which cut internal b-1,4-glucosidic bonds; (2) exocellobiohydrolases that cut the dissaccharide cellobiose from the nonreducing end of the cellulose polymer chain; (3) b-1,4-glucosidases which hydrolyze the cellobiose and other short cello-oligosaccharides to glucose. Hydrolysis of 1,4-b-d-glucosidic linkages in cellulose and cellotetraose, releasing cellobiose from the non- reducing ends of the chains. Endohydrolysis of 1,4-b-D-xylosidic linkages in xylans.
55	Myrosinase (thioglucoside glucohydratase)		Degradation of glucosinolates (glucose residue linked by a thioglucoside bound to an amion acid derivative) to glucose, sulphate and any of the products: thiocyanates, isothiocyanates, nitriles, epithionitriles or oxazolidine-2-thiones. Thioglucoside + H₂O = Thiol + sugar.
56	Alanine racemase	Biosynthesis Of Cyclosporin A.	Along with D-Ala-D-Ala ligase it makes up the D-Ala branch of the peptidoglycan biosynthetic route. L Alanine = D Alanine
57.	isomaylase		Hydrolysis of 1,6-a-D-glucosidic branch linkages in glycogen, amylopectin and their b-limits dextrins.
58	chitinase A		Hydrolysis of b-1-4 linkges of N - Acetyl D-Glucosamine polymers of chitin.
59	phospholipase C (phosphoinositide-specific delta 1)		Acts as a signal transducer that generates two secondary messengers namely Inositol 1,4,5 triphosphate and Diacyl glycerol. 1-Phosphatidyl D- Myo Inositol 4,5 bisphosphate + H₂O = D-Myoinositol 1,4,5 triphosphate + Diacylglycerol.
60	phosphoenol pyruvate carboxylase	Tricarboxylic Acid Cycle.	Interconverts oxaloacetate, and Phosphoenol pyruvate, both four-carbon dicarboxylic acids in the tricarboxylic acid cycle. Orthophosphate + oxaloacetate = phosphoenolpyruvate + H₂O + CO₂
61	Lux F gene product	related to luciferase.	Non fluorescent flavoprotein with limited sequence homology to luciferase but possess luciferase activity.
62	tRNA- Guanine transglycosylase		Exchanges the guanine residue with 7-aminomethyl-7- deazaguanine in tRNAs with gu(n) anticodons (tRNA-asp, -asn, -his and -tyr). After this exchange, a cyclopentendiol moiety is attached to the 7-aminomethyl group of 7-deazaguanine, resulting in the hypermodified nucleoside queuosine (q) (7-(((4,5-cis- dihydroxy-2-cyclopenten-1-y1)amino)methyl)-7-deazaguanosine). Trna guanine + queuine = trna queuine + guanine.
63	Pyruvate phosphate dikinase		Catalyzes reversible phosphorylationof pyruvate and phosphate in the direction of ATP synthesis. ATP + Pyruvate + Phosphate = AMP + PEP + Diphosphate
64	ribonucleotide reductase R1 protein	First Reaction In The Dna Replication Pathway.	Catalyzes the biosynthesis of deoxyribonucleotides from the corresponding ribonucleotides, precursors that are necessary for dna synthesis. R1 contains the binding sites for both substrates and allosteric effectors and carries out the actual Reduction of the ribonucleotide. 2'-deoxyribonucleoside diphosphate + oxidized thioredoxin + H₂O = Ribonucleoside diphosphate + reduced thioredoxin.
65	FR-1 protein (Fibroblast growth factor induced reductase protein)		Induced by fibroblast growth factor, 70% identical to the human aldose reductase. A potent aldose reductase inhibitor. Plays a role in the regulationof cell cycle