Literature summary for 2.4.1.18 extracted from

Pal, K.; Kumar, S.; Sharma, S.; Garg, S.K.; Alam, M.S.; Xu, H.E.; Agrawal, P.; Swaminathan, K.
Crystal structure of full-length Mycobacterium tuberculosis H37Rv glycogen branching enzyme: insights of N-terminal beta-sandwich in substrate specificity and enzymatic activity (2010), J. Biol. Chem., 285, 20897-20903.

Cloned(Commentary)

Cloned (Comment)	Organism
expression in Escherichia coli	Mycobacterium tuberculosis

Crystallization (Commentary)

Crystallization (Comment)	Organism
crystal structure of full-length protein at 2.33 A resolution. The enzyme contains four domains: N1 beta-sandwich, N2 beta-sandwich, a central (beta/alpha)8 domain that houses the catalytic site, and a C-terminal beta-sandwich. The N1 beta-sandwich, which is formed by the first 105 amino acids and superimposes well with the N2 beta-sandwich, has an influence in substrate binding in the amylase assay	Mycobacterium tuberculosis

Crystallization (Comment)

Organism

crystal structure of full-length protein at 2.33 A resolution. The enzyme contains four domains: N1 beta-sandwich, N2 beta-sandwich, a central (beta/alpha)8 domain that houses the catalytic site, and a C-terminal beta-sandwich. The N1 beta-sandwich, which is formed by the first 105 amino acids and superimposes well with the N2 beta-sandwich, has an influence in substrate binding in the amylase assay

Mycobacterium tuberculosis

Protein Variants

Protein Variants	Comment	Organism
additional information	a mutant lacking the N1 domain, i.e. lacking N-terminal residues 1-108, shows about 30% decrease in specific activity	Mycobacterium tuberculosis

Inhibitors

Inhibitors	Comment	Organism	Structure
additional information	not inhibitory: ADP, ADP glucose, tunicamycin, castenospermine, nojirimycin, or acarbose	Mycobacterium tuberculosis

KM Value [mM]

KM Value [mM]	KM Value Maximum [mM]	Substrate	Comment	Organism	Structure
additional information	-	additional information	Km-value for amylose is 0.56 mg/ml, wild-type, 25°C, pH 7.0. Km value for mutant lacking N1 domain is 0.33 mg/ml	Mycobacterium tuberculosis

Organism

Organism	UniProt	Comment	Textmining
Mycobacterium tuberculosis	P9WN45	-	-
Mycobacterium tuberculosis H37Rv	P9WN45	-	-

Specific Activity [micromol/min/mg]

Specific Activity Minimum [µmol/min/mg]	Specific Activity Maximum [µmol/min/mg]	Comment	Organism
42	-	mutant lacking the N1 domain, i.e. lacking N-terminal residues 1-108, pH 7.0, 25°C	Mycobacterium tuberculosis
63.75	-	wild-type, pH 7.0, 25°C	Mycobacterium tuberculosis

Substrates and Products (Substrate)

Substrates	Comment Substrates	Organism	Products	Comment (Products)	Rev.
amylose	-	Mycobacterium tuberculosis	amylose containing alpha-1,6-glucosidic linkages	-	?
amylose	-	Mycobacterium tuberculosis H37Rv	amylose containing alpha-1,6-glucosidic linkages	-	?
additional information	two-step reaction mechanism for the amylase activity, i.e. 1-4 bond breakage, and isomerization, i.e. 1-6 bond formation, which occur in the same catalytic pocket	Mycobacterium tuberculosis	?	-	?
additional information	two-step reaction mechanism for the amylase activity, i.e. 1-4 bond breakage, and isomerization, i.e. 1-6 bond formation, which occur in the same catalytic pocket	Mycobacterium tuberculosis H37Rv	?	-	?
starch	-	Mycobacterium tuberculosis	starch containing alpha-1,6-glucosidic linkages	-	?
starch	-	Mycobacterium tuberculosis H37Rv	starch containing alpha-1,6-glucosidic linkages	-	?

Synonyms

Synonyms	Comment	Organism
GlgB	-	Mycobacterium tuberculosis

Turnover Number [1/s]

Turnover Number Minimum [1/s]	Turnover Number Maximum [1/s]	Substrate	Comment	Organism	Structure
0.068	-	amylose	mutant lacking N1 domain, pH 7.0, 25°C	Mycobacterium tuberculosis
0.15	-	amylose	wild-type, pH 7.0, 25°C	Mycobacterium tuberculosis