CHLOROPHYLL-SENSITIZED REDUCTION OF PLASTOQUINONE BY ASCORBIC ACID AND QUENCHING OF CHLOROPHYLL-FLUORESCENCE BY PLASTOQUINONE

1. Photochemical reduction of plastoquinone by ascorbic acid inethanol was sensitized with some derivatives of chlorophyll.The order of effectiveness was as follows: allomerized chlorophylla > chlorophyllin a > chlorophyll a > chlorophyll b> pheophytin a.
2. Quenching of the fluorescence of chlorophylla by plastoquinonewas observed. The quenching constant calculatedwas 71 litreper mole.

¹Contribution No. 159 from the Department of Biology, Facultyof Science, Kyushu University. Supported in part by a grant-in-aidfor Fundamental Scientific Research from the Ministry of Education. ²Present address: Biological Laboratory, General Education Department,Kyushu University, Ropponmatsu, Fukuoka. ³Present address: Biological Institute, Daiichi College of PharmaceuticalSciences, Tamagawa-machi, Takamiya, Fukuoka.     

FORMATION OF SEROTONIN BY ISOLATED SEROTONIN-CONTAINING NEURONS AND BY ISOLATED NON-AMINE-CONTAINING NEURONS

Isolated giant serotonin-containing neurons of the cerebral ganglia of Helix pomatia were shown to produce serotonin when incubated with 5-hydroxytryptophan (5-HTP) whereas cells of the buccal ganglia, which are non-amine-containing cells did not. The rate of production was comparable to that for Ach in the isolated neurons of Aplysia. The significance of these results is discussed.     

THE DIGESTION AND INACTIVATION OF MALTASE BY TRYPSIN AND THE SPECIFICITY OF MALTASES

1. The maltase of saliva and that of E. coli (B. coli communis) hydrolyze maltose but not α-methylglucoside or sucrose and are therefore to be considered glucomaltases. 2. Maltase is rapidly and completely inactivated and digested by trypsin.     

BREAKDOWN OF TIMBER BY ASCOMYCETES AND FUNGI IMPERFECTI

Soft rot of wood is caused by certain species of Ascomycetes and Fungi Imperfecti The fungal hyphae typically run spirally in the central zone of the secondary xylem walls, where they give rise to cavities with pointed ends.
The fungi causing soft rot are cellulose-attacking species which initiate attack in the less heavily lignified parts of the walls of the wood elements. The rate of attack is increased when inorganic nutrient salts are added to the wood.
Under laboratory conditions Chaetomium globosum can cause severe decay of hardwoods.
Soft rot causes serious deterioration of timber in water-cooling towers and is therefore of considerable economic importance.