Literature summary for 2.4.1.25 extracted from

Jung, J.; Jung, T.; Seo, D.; Yoon, S.; Choi, H.; Park, B.; Park, C.; Woo, E.
Structural and functional analysis of substrate recognition by the 250s loop in amylomaltase from Thermus brockianus (2011), Proteins, 79, 633-644.

Search for more literature for 2.4.1.25

Cloned(Commentary)

Cloned (Comment)	Organism
-	Thermus brockianus

Crystallization (Commentary)

Crystallization (Comment)	Organism
to 2.3 A resolution. Structure shows a pattern of conformational flexibility in the 250s loop with higher B-factor. The conformational flexibility of the loop may be involved in substrate binding in the GH77 family	Thermus brockianus

Protein Variants

Protein Variants	Comment	Organism
F251G	mutation results in significantly lower glucose production but increased maltose production from maltopentose substrates, showing an altered substrate-binding affinity	Thermus brockianus
Q256G	mutation results in increased Km for maltotriose and a sharp decrease of the transglycosylation factor for maltose	Thermus brockianus
W258G	mutant shows neither cyclization nor coupling activity, suggesting that residue Trp258 plays an essential role in all catalytic activities including hydrolysis and transglycosylation activities	Thermus brockianus

KM Value [mM]

KM Value [mM]	KM Value Maximum [mM]	Substrate	Comment	Organism	Structure
2	-	maltotriose	wild-type, pH 6.0, 70°C	Thermus brockianus
5.8	-	maltotriose	mutant F251G, pH 6.0, 70°C	Thermus brockianus
9.5	-	maltotriose	mutant W258G, pH 6.0, 70°C	Thermus brockianus
165	-	maltotriose	mutant Q256G, pH 6.0, 70°C	Thermus brockianus

Organism

Organism	UniProt	Comment	Textmining
Thermus brockianus	Q2VJA0	-	-

Substrates and Products (Substrate)

Substrates	Comment Substrates	Organism	Products	Comment (Products)	Rev.	Reac.
maltotriose	-	Thermus brockianus	maltooligosaccharides	-	?

Turnover Number [1/s]

Turnover Number Minimum [1/s]	Turnover Number Maximum [1/s]	Substrate	Comment	Organism	Structure
0.0017	-	maltotriose	mutant F251G, pH 6.0, 70°C	Thermus brockianus
0.005	-	maltotriose	mutant W258G, pH 6.0, 70°C	Thermus brockianus
0.015	-	maltotriose	wild-type, pH 6.0, 70°C	Thermus brockianus
0.08	-	maltotriose	mutant Q256G, pH 6.0, 70°C	Thermus brockianus

kcat/KM [mM/s]

kcat/KM Value [1/mMs^-1]	kcat/KM Value Maximum [1/mMs^-1]	Substrate	Comment	Organism	Structure
0.00035	-	maltotriose	mutant F251G, pH 6.0, 70°C	Thermus brockianus
0.00048	-	maltotriose	mutant Q256G, pH 6.0, 70°C	Thermus brockianus
0.00048	-	maltotriose	mutant W258G, pH 6.0, 70°C	Thermus brockianus
0.007	-	maltotriose	wild-type, pH 6.0, 70°C	Thermus brockianus

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Release 2023.1 (January 2023)