1. Alcohol oxidase (alcohol : oxygen oxidoreductase) of a thermophilic methanol-utilizing yeast, Hunsenula polymorpha DL-1 , was isolated in crystalline form.2. This alcohol oxidase of H . polymorphu was more stable to heat than was the enzyme of Kloeckera sp. This difference in heat stability is compatible with the difference in growth temperatures for both yeasts.3. The crystalline alcohol oxidases of both yeasts oxidized the lower primary alcohols ((2-2 to C-4) as well as methanol. The apparent K,,, values for the methanol of Kloeckera and H. polymorpha enzymes were 0.44 and 0.23 mM, respectively. The enzymes could also oxidize formaldehyde to formate, and were inactivated by relatively low concentrations of hydrogen peroxide.4. The molecular weight for both enzymes was calculated to be about 670000. Each enzyme is composed of eight identical subunits (molecular weight 83000) and contains eight moles of FAD as the prosthetic group. The NH,-terminal and COOH-terminal amino acids of H . polymorpha enzyme were identified as alanine and phenylalanine, respectively. The octameric subunits model of each enzyme was confirmed by electron micrographs, which showed an octad aggregate, composed of two tetragons face to face.

Abstract.A way to write proof scores showing that distributed systems have invariant properties in algebraic specification languages is described, which has been devised through several case studies. The way makes it possible to divide a formula stating an invariant property under discussion into reasonably small ones, each of which is proved by writing proof scores individually. This relieves the load to reduce logical formulas and can decrease the number of subcases into which the case is split in case analysis.

The metabolism of polyethylene glycol (PEG) was investigated with a synergistic, mixed culture of Flavobacterium and Pseudomonas species, which are individually unable to utilize PEGs. The PEG dehydrogenase linked with 2,6dichlorophenolindophenol was found in the particulate fraction of sonic extracts and catalyzed the formation of a 2,4-dinitrophenylhydrazine-positive compound, possibly an aldehyde. The enzyme has a wide substrate specificity towards PEGs: from diethylene glycol to PEG 20,000. Km values for tetraethylene glycol (TEG), PEG 400, and PEG 6,000 were 11, 1.7, and 15 mM, respectively. The metabolic products formed from TEG by intact cells were isolated and identified by combined gas chromatography-mass spectrometry as triethylene glycol and TEGmonocarboxylic acid plus small amounts of TEG-dicarboxylic acid, diethylene glycol, and ethylene glycol. From these enzymatic and analytical data, the following metabolic pathway was proposed for PEG: HO(CH2CH20)nCH2CH20H-+ HO(CH2CH20)nCH2CHO-* HO(CH2CH20)nCH2COOH-HO(CH2CH2-O),-0CH2CH20H.

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