Starch-utilizing mutants of Escherichia coli which can grow well on starch or amylose as the sole carbon source were isolated. Themaximalviable cell numberof the starch-utilizing mutants on the polysaccharide media reached the same level (4 x 109 cells/ml) as that with glucose medium after incubation for 24 hours at 37°C. The isolated mutants could produce more intracellular a-amylase than the wild-type strain, and the enzyme activity was detected in the extracellular fluid. Polyacrylamide gel electrophoresis showed that the intracellular and extracellular enzymes had similar electrophoretic mobilities. These observations suggested that the ability of growth on the polysaccharide media was due to the excreted a-amylase, which appeared to be identical with the intracellular enzyme.

A plasmid, YRp7, carrying the yeast TRP1 gene transformed a trpl strain JH of Saccharomyces cerevisiae without spheroplasting. The transformation conditions were that intact cells were incubated with the plasmid DNA in chilled CaCl2 solution and then the incubation temperature was raised. The transformation frequency changed markedly with the CaCl2 concentration of the solution and the temperature rise after incubation at 0°. The optimal CaCl2 concentration and temperature for strain JH were 200 him and 37°, respectively. Polyethylene glycol and the age of cells showed little effect on the

A new type of mutant unable to reduce 2,3,5-triphenyltetrazolium chloride (TTC) was isolated from miitagenized cells of Saccharomycescerevisiae. These TTC"mutants were respirationcompetent although most TTC" mutants reported so far are respiration-deficient. The isolated mutants were also uracil auxotrophic, and genetic analysis indicated that a recessive mutation took place on a single gene tightly linked to the ura2 gene or in the ura2 gene in all these mutants. Moreover, we found that authentic ura mutants (ural to uraS) also exhibited the TTC" phenotype while other auxotrophic mutants tested were of the TTC+phenotype. These findings suggest that yeast cells have a TTCreduction system related to uracil metabolism besides that related to respiratory potential.

* Chiba -kurimoto laboratory Co ., ltd.)To classify the flavors of Shochu and White spirits, we analyzed 20 volatile compounds by head space solid phase micro extraction (SPME), 7 volatile compounds by direct head space analysis, and 2volatile compounds by enzymatic analysis among 28 Shochu-otsu, 2 Blended shochu,3 Shochu-ko, 4 Baijiu (Chinese liquor), 3 Vodka, 3 White rum, 3 Gin, and 4 other Spirits. Acidity, TBA-value, and pH were also determined. In a cluster analysis using these 32 elements, Shochu-otsu was distinguished from the other spirits. In a stepwise discriminant analysis procedure using acetic acid, ethyl acetate, 3-methyl-1-butanol, and dodecanol, they were classified into three groups : Shochu-otsu, Light spirits (Shochu-ko, Blended shochu, Vodka and White rum), and Baijiu. It was also possible to classify Shochu-otsu into six raw material categories by a discriminant analysis using methanol, 1-propanol, 2-methyl-1-propanol, and ethyl octanoate.

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