1ji2

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Improved X-ray Structure of Thermoactinomyces vulgaris R-47 alpha-Amylase 2Improved X-ray Structure of Thermoactinomyces vulgaris R-47 alpha-Amylase 2

Structural highlights

1ji2 is a 2 chain structure with sequence from Atcc 43649. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Ligands:
Activity:Neopullulanase, with EC number 3.2.1.135
Resources:FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

[NEPU2_THEVU] Hydrolyzes pullulan efficiently but only a small amount of starch. Endohydrolysis of 1,4-alpha-glucosidic linkages in pullulan to form panose. Cleaves also (1-6)-alpha-glucosidic linkages to form maltotriose.

Evolutionary Conservation

Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.

Publication Abstract from PubMed

The X-ray crystal structures of Thermoactinomyces vulgaris R-47 alpha-amylase 1 (TVAI) and alpha-amylase 2 (TVAII) have been determined at 1.6 A and 2.3 A resolution, respectively. The structures of TVAI and TVAII have been refined, R-factor of 0.182 (R(free)=0.206) and 0.179 (0.224), respectively, with good chemical geometries. Both TVAI and TVAII have four domains, N, A, B and C, and all very similar in structure. However, there are some differences in the structures between them. Domain N of TVAI interacts strongly with domains A and B, giving a spherical shape structure to the enzyme, while domain N of TVAII is isolated from the other domains, which leads to the formation of a dimer. TVAI has three bound Ca ions, whereas TVAII has only one. TVAI has eight extra loops compared to TVAII, while TVAII has two extra loops compared to TVAI. TVAI can hydrolyze substrates more efficiently than TVAII with a high molecular mass such as starch, while TVAII is much more active against cyclodextrins than TVAI and other alpha-amylases. A structural comparison of the active sites has clearly revealed this difference in substrate specificity.

Crystal structures and structural comparison of Thermoactinomyces vulgaris R-47 alpha-amylase 1 (TVAI) at 1.6 A resolution and alpha-amylase 2 (TVAII) at 2.3 A resolution.,Kamitori S, Abe A, Ohtaki A, Kaji A, Tonozuka T, Sakano Y J Mol Biol. 2002 Apr 26;318(2):443-53. PMID:12051850[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

See Also

References

  1. Kamitori S, Abe A, Ohtaki A, Kaji A, Tonozuka T, Sakano Y. Crystal structures and structural comparison of Thermoactinomyces vulgaris R-47 alpha-amylase 1 (TVAI) at 1.6 A resolution and alpha-amylase 2 (TVAII) at 2.3 A resolution. J Mol Biol. 2002 Apr 26;318(2):443-53. PMID:12051850 doi:10.1016/S0022-2836(02)00111-0

1ji2, resolution 2.30Å

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