Isolation, crystallization in the macrogravitation field, preliminary X-ray investigation of uridine phosphorylase from Escherichia coli K-12.
Uridine phosphorylase (UPH) from Escherichia coli K-12 has been purified to near homogeneity from a strain harbouring the udp gene, encoding UPH, on a multicopy plasmid. UPH was purified to electrophoretic homogeneity with the specific activity 230 units/mg with a recovery of 80%, yielding 120 mg of enzyme from 3g cells. Crystals of enzyme suitable for X-ray diffraction analysis were obtained in a preparative ultracentrifuge. The packing of the molecules in the crystals may be described by the space group P2(1)2(1)2(1) with the unit cell constants a = 90.4; b = 128.8; c = 136.8 A. There is one molecule per asymmetric unit, Vm = 2.4. These crystals diffract to at least 2.5-2.7 A resolution. The hexameric structure of UPH was directly demonstrated by electron microscopy study and image processing.
Mikhailov
A M
AM
Institute of Crystallography Academy of Sciences of the USSR, Moscow.
Smirnova
E A
EA
Tsuprun
V L
VL
Tagunova
I V
IV
Vainshtein
B K
BK
Linkova
E V
EV
Komissarov
A A
AA
Siprashvili
Z Z
ZZ
Mironov
A S
AS
D003460:Crystallization; D004926:Escherichia coli / Q000201:enzymology* / Q000235:genetics; D011487:Protein Conformation; D014543:Uridine Phosphorylase / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification*; D014961:X-Ray Diffraction
D014543:Uridine Phosphorylase