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F Frolow

Publications and source records attributed to F Frolow.

42 records · Page 3Linked to original sources
PubMed1988

Purification and crystallization of a dimeric form of acetylcholinesterase from Torpedo californica subsequent to solubilization with phosphatidylinositol-specific phospholipase C.

A dimeric form of acetylcholinesterase from Torpedo californica was purified to homogeneity by affinity chromatography subsequent to solubilization with a phosphatidylinositol-specific phospholipase C of bacterial origin. Bipyramidal crystals of the enzyme were obtained from solutions in polyethylene glycol 200. The crystals diffract to 2.0 A (1 A = 0.1 nm) resolution. They were found to be orthorhombic, space group P2221, with a = 163.4(+/- 0.2) A, b = 112.1(+/- 0.2) A, c = 81.3(+/- 0.1) A.

Acetylcholinesterase↗
PubMed1988

The three-dimensional structure of a DNA duplex containing looped-out bases.

Unpaired bases in DNA have been assigned a possible role in the mechanism of frameshift mutagenesis in sequences with repeated base pairs. They also occur in quasipalindromic DNA sequences, which have been implicated in mutagenesis where there are no repeated base pairs, through the formation of single-stranded hairpin loops. The conformation of unpaired bases in DNA has been the subject of numerous thermodynamic as well as high resolution NMR (nuclear magnetic resonance) studies (reviewed in ref. 4). The NMR studies in solution have shown that the duplex of the tridecamer DNA fragment d(CGCAGAATTCGCG) remains intact, and that the unpaired adenosines are stacked into the duplex. Having crystallized this oligonucleotide and determined its structure, we find its conformation in the crystal is close to that of a B-DNA duplex, with the two additional adenosines looped out from the double helix and causing little disruption of the rest of the structure.

Base Composition↗
PubMed1988

Crystallization of halophilic malate dehydrogenase from Halobacterium marismortui.

Malate dehydrogenase from the extreme halophile Halobacterium marismortui crystallizes in highly concentrated phosphate solution in space group 12 with cell dimensions a = 113.8 A, b = 122.8 A, c = 126.7 A, beta = 98.1 degrees. The halophilic enzyme was found to be unstable at lower concentrations of phosphate. It associates with unusually large amounts of water and salt, and the combined particle volume shows a tight fit in the unit cell.

Halobacterium↗
PubMed1987

Single crystals of large ribosomal particles from Halobacterium marismortui diffract to 6 A.

Large, well-ordered three-dimensional crystals of 50 S ribosomal subunits from Halobacterium marismortui have been obtained by seeding. The crystals have been characterized with synchrotron X-ray radiation as monoclinic, space group P2(1), with unit cell dimensions of a = 182(+/- 5) A, b = 584(+/- 10) A, c = 186(+/- 5) A, beta = 109 degrees. At 4 degrees C, the crystals (0.6 mm X 0.6 mm X 0.1 mm) diffract to 6 A resolution and are stable in the synchrotron beam for several hours. Compact packing is reflected from the crystallographic unit cell parameters and from electron micrographs of positively stained thin sections of embedded crystals.

Crystallization↗
PubMed1986

Characterization of single crystals of the large ribosomal particles from a mutant of Bacillus stearothermophilus.

Single, three-dimensional crystals of 50 S ribosomal subunits, from a mutant of Bacillus stearothermophilus that lacks the protein L11, have been characterized using a synchrotron X-ray source. The crystals of the mutated particles grow under the same conditions and are isomorphous to those of the wild type of the same bacteria. They are orthorhombic, contain at least one 2-fold screw axis, and have unit cell dimensions of a = 350(+/- 10) A, b = 670(+/- 10) A, and c = 910(+/- 10) A. They diffract to 15 to 18 A resolution at 4 degrees C and are stable in the synchrotron beam for several hours.

Crystallography↗