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Lipase from Pseudomonas glumae has been purified and crystallized in two forms, using the hanging drop method of vapour diffusion at 4 degrees C and 15 degrees C. Both forms grew at pH 9.0 from 0.1 M-Tris buffer in the presence of 10% (v/v) acetone. Form 1 was crystallized from 27 to 29% polyethylene glycol in the presence of less than 0.5% (v/v) n-dodecyl-beta-D-glucopyranoside. Form 2 was grown from 17 to 19% ammonium sulphate in the presence of 1% n-octyl-beta-D-glucopyranoside. Form 1 is orthorhombic with space group P2(1)2(1)2(1), and cell dimensions of a = 158.1 A, b = 158.6 A, c = 63.4 A, Form 2 is tetragonal with space group P4(1)2(1)2 (or P4(3)2(1)2) and cell dimensions of a = 89.3 A, c = 180.4 A. Form 1 probably has four molecules per asymmetric unit and diffracts to at least 2.5 A. Form 2 has two molecules per asymmetric unit and diffracts to at least 3.0 A.

A combined crystal-structure determination and NMR analysis of the octanucleotide d(ATGCGCAT)2 is reported. The X-ray analysis shows that the structure is A-form duplex in crystal state. The NMR study shows that in solution this sequence is B-type. The conformational results from each technique are presented in detail. The implications of these findings in terms of conformational flexibility and ligand binding are discussed.

The three-dimensional structure of a complex between the dodecanucleotide d(CGCGAATTCGCG) and the anti-trypanocidal drug berenil, has been determined to a resolution of 2.5 A. The structure has been solved by molecular replacement and refined to an R factor of 0.177. A total of 49 water molecules have been located. The drug is bound at the 5'-AAT-3' region of the oligonucleotide. At one end of the drug the amidinium group is in hydrogen-bonded contact with N3 of the adenine base complementary to the thymine of the AAT. The other amidinium group does not make direct interactions with the DNA. Instead, a water molecule mediates between them. This is in hydrogen-bonded contact with an amidinium nitrogen atom, N3 of the 5' end adenine base and the ring oxygen atom of an adjacent deoxyribose. Molecular mechanics calculations have been performed on this complex, with the drug at various positions along the sequence. These show that the observed position is only 0.8 kcal/mol higher in energy than the best position. It is suggested that there is a broad energy well in the AATT region for this drug, and that water molecules as well as the neighbouring sequence, will determine precise positioning. More general aspects of minor groove binding are discussed.

An NAD(P)H quinone reductase isolated from Walker rat 256 carcinoma cells has been crystallized in a form suitable for high-resolution structural analysis. The crystals belong to orthorhombic space group P2(1)2(1)2(1) with cell parameters a = 168.15 A, b = 105.09 A and c = 67.38 A and contain four monomeric or two dimeric enzyme molecules per asymmetric unit. Diffraction extends beyond 2.3 A resolution.

This study focuses on consumers' level of knowledge, opinions, and degree of preparedness concerning selected practices and regulations of the funeral industry. Questionnaires were returned by 75 percent of the sample of faculty and staff at a large university. Opinions of respondents rejected the status quo concerning various practices and regulations of the funeral industry, indicating a desire to support newly suggested changes in the industry. Preparedness scores indicated that almost 9 out of 10 of the respondents were quite unprepared for their own funerals. The mean achievement score regarding knowledge as measured by the Consumer Funeral Test, which was developed for this study, was 4.0, representing 57 percent correct. Significant statistical relationships existed between knowledge scores and the age, education, and sex of the respondents; those who were older and had more education scored higher, and men scored higher than women. No relationships existed, however, among knowledge, opinion, and preparedness scores and the demographic variables of age, education, income, sex, and religion, raising the fundamental question of the value of funeral information programs for consumers.