1K6A

Structural studies on the mobility in the active site of the Thermoascus aurantiacus xylanase I

Replaces:  1FXM

Summary for 1K6A

• Entry DOI: 10.2210/pdb1k6a/pdb
• Related: 1fxm 1tax
• Descriptor: xylanase I (2 entities in total)
• Functional Keywords: alternate conformations, active site mobility, hydrolase
• Biological source: Thermoascus aurantiacus
• Total number of polymer chains: 1
• Total formula weight: 32907.74

Authors

Lo Leggio, L.,Kalogiannis, S.,Eckert, K.,Teixeira, S.C.M.,Bhat, M.K.,Andrei, C.,Pickersgill, R.W.,Larsen, S. (deposition date: 2001-10-15, release date: 2002-07-03, Last modification date: 2024-11-06)

Primary citation

Lo Leggio, L.,Kalogiannis, S.,Eckert, K.,Teixeira, S.C.,Bhat, M.K.,Andrei, C.,Pickersgill, R.W.,Larsen, S.
Substrate specificity and subsite mobility in T. aurantiacus xylanase 10A.
FEBS LETT., 509:303-308, 2001

PubMed Abstract: The substrate specificity of Thermoascus aurantiacus xylanase 10A (TAX) has been investigated both biochemically and structurally. High resolution crystallographic analyses at 291 K and 100 K of TAX complexes with xylobiose show that the ligand is in its alpha anomeric conformation and provide a rationale for specificity on p-nitrophenyl glycosides at the -1 and -2 subsites. Trp 275, which is disordered in uncomplexed structures, is stabilised by its interaction with xylobiose. Two structural subsets in family 10 are identified, which differ by the presence or absence of a short helical stretch in the eighth betaalpha-loop of the TIM barrel, the loop bearing Trp 275. This structural difference is discussed in the context of Trp 275 mobility and xylanase function.

PubMed: 11741607
DOI: 10.1016/S0014-5793(01)03177-5

Experimental method

X-RAY DIFFRACTION (1.14 Å)