An amylose antiparallel double helix at atomic resolution.
In the crystal structure of the polyiodide complex (p-nitrophenyl-alpha-maltohexaose(2)) . Ba(I(3))(2) . 22H(2)O, the maltohexaose units form an antiparallel, left-handed double helix with O-2 ... O-3 and O-6 ... O-6 hydrogen bonding and a central cavity that encloses two triiodide units. This structure contrasts with the parallel, left-handed double helix with no central cavity proposed for the A-and B-starch helix and the left-handed single helix in V-amylose and may be relevant for the stabilization of glycogen Structure.
Hinrichs
W
W
Büttner
G
G
Steifa
M
M
Betzel
C
C
Zabel
V
V
Pfannemüller
B
B
Saenger
W
W