The compressive behavior of adamantane and its secondary monosubstituted derivatives; adamantanone, 2-methyladamantane, and 2-bromoadamantane was measured at various temperatures in a piston-cylinder apparatus. A first-order solid-solid phase transition was found under pressure in each system. The transition pressures, the equilibrium pressures, the volume changes, and the entropy changes for the transition were determined. The compression data for the low pressure phases were fitted to an equation of the form −ΔV⁄V0=a0+a1P+a2P2. The effects of substituent groups on the entropy changes of the transitions of these molecular crystals were discussed.

Organic solvent-tolerant Pseudomonas aeruginosa LST-03 secretes an organic solvent-stable lipase, LST-03 lipase. The gene of the LST-03 lipase (Lip9) and the gene of the lipase-specific foldase (Lif9) were cloned and expressed in Escherichia coli. In the cloned 2.6 kbps DNA fragment, two open reading frames, Lip9 consisting of 933 nucleotides which encoded 311 amino acids and Lif9 consisting of 1,020 nucleotides which encoded 340 amino acids, were found. The overexpression of the lipase gene (lip9) was achieved when T7 promoter was used and the signal peptide of the lipase was deleted. The expressed amount of the lipase was greatly increased and overexpressed lipase formed inclusion body in E. coli cell. The collected inclusion body of the lipase from the cell was easily solubilized by urea and activated by using lipase-specific foldase of which 52 or 58 amino acids of N-terminal were deleted. Especially, the N-terminal methionine of the lipase of which the signal peptide was deleted was released in E. coli and the amino acid sequence was in agreement with that of the originally-produced lipase by P. aeruginosa LST-03. Furthermore, the overexpressed and solubilized lipase of which the signal peptide was deleted was more effectively activated by lipase-specific foldase.

Fluorescence spectra of 1,2-di(9-anthryl)ethane (1), 1,3-di(9-anthryl)propane (2), and 9,9′-bianthryl (3) have been studied at high pressures up to 50 kbar both in crystalline state and in PMMA matrix. In the case of 1 and 2 in crystalline state, the excimer emissions appear reversibly at high pressures accompanied by the reversible red shifts. While in PMMA the fluorescence spectra assigned as locally excited state are observed, whose peak shifts are quite analogous to that of anthracene in the same matrix. As for 3, a new band also appears at high pressure which is similar to the intramolecular charge-transfer band. Possible interpretations of the pressure effects are discussed.

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