The light saturated rate of photosystem I-dependent electron transport (ascorbate/dichlorophenol-indophenol --> methyl vilogen in presence of 1 micromolar 3-[3,4-dichlorophenyl]-1,1-dimethyl urea [DCMU]) was increased by a high concentration of DCMU added to broken and uncoupled chloroplasts isolated from pea (Pisum sativum). At 50 micromolar DCMU, the increase was around 50%. No stimulation wa...

Four mutant strains of Euglena gracilis have been isolated after treatment of wild type cells with ultraviolet light or the chemical mutagen nitrosoguanidine. None of the mutants is capable of autotrophic growth or photosynthetic carbon dioxide fixation. The mutant strains contain normal amounts of the enzymes of the reductive pentose phosphate cycle and are qualitatively similar to the wild ty...

The effect of a series of redox indicators and systems has been tested with a suspension of luminous bacteria (B. fischeri) in M/4 phosphate buffer of P(H) = 7.6. The indicators behave as expected from their position in the redox series, the most positive being reduced rapidly even in presence of air and before luminescence of the bacteria disappears, those of intermediate position at the time ...

This paper describes the functional characterization of the xyloside transporter, XylP, of Lactobacillus pentosus with the aid of a spectroscopy-based assay system. In order to monitor the transport reaction, the natural xyloside isoprimeverose, a building block of hemicellulose, and the analogue methyl-isoprimeverose were chemically synthesized by a new and efficient procedure. The XylP protei...

In a previous paper (1) a calorimetric phenol oxidase method was presented which utilizes catechol as a mediator and in which the oxidation of a leucoindophenol is followed photometrically over a very short time interval. During the development of this method it was found that the same basic method and technique were applicable to the determination of peroxidase. In the latter case, oxidation o...