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1Q4N

Structural studies of Phe256Trp of human salivary alpha-amylase: implications for the role of a conserved water molecule and its associated chain in enzyme activity

Entity
Entity IDChain IDDescriptionTypeChain lengthFormula weightNumber of moleculesDB Name (Accession)Biological sourceDescriptive keywords
1A
(X)
Alpha-amylase, salivarypolymer49655994.31UniProt (P04745)
Pfam (PF00128)
Pfam (PF02806)
UniProt (by SIFTS) (P0DUB6)
Homo sapiens (human)1,4-alpha-D-glucan glucanohydrolase
2B
(X)
CALCIUM IONnon-polymer40.11Chemie (CA)
3C
(X)
CHLORIDE IONnon-polymer35.51Chemie (CL)
4D
(X)
TRIS(HYDROXYETHYL)AMINOMETHANEnon-polymer163.21Chemie (TAM)
5E
(X)
waterwater18.0324Chemie (HOH)
Sequence modifications
X: 1 - 496 (UniProt: P04745)
PDBExternal DatabaseDetails
Trp 256Phe 271engineered mutation
Sequence viewer
Contents of the asymmetric unit
PolymersNumber of chains1
Total formula weight55994.3
Non-Polymers*Number of molecules3
Total formula weight238.7
All*Total formula weight56233.0
*Water molecules are not included.

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PDB entries from 2025-07-16

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