Light driven CO2 fixation by using cyanobacterial photosystem I and NADPH-dependent formate dehydrogenase.

The ultimate goal of this research is to construct a new direct CO2 fixation system using photosystems in living algae. Here, we report light-driven formate production from CO2 by using cyanobacterial photosystem I (PS I). Formate, a chemical hydrogen carrier and important industrial material, can be produced from CO2 by using the reducing power and the catalytic function of formate dehydrogenase (FDH). We created a bacterial FDH mutant that experimentally switched the cofactor specificity from NADH to NADPH, and combined it with an in vitro-reconstituted cyanobacterial light-driven NADPH production system consisting of PS I, ferredoxin (Fd), and ferredoxin-NADP(+)-reductase (FNR). Consequently, light-dependent formate production under a CO2 atmosphere was successfully achieved. In addition, we introduced the NADPH-dependent FDH mutant into heterocysts of the cyanobacterium Anabaena sp. PCC 7120 and demonstrated an increased formate concentration in the cells. These results provide a new possibility for photo-biological CO2 fixation.

Defining the culture and attitude towards dietary management actions in people undergoing haemodialysis.

OBJECTIVES: The present study was designed to clarify the structure of culture and the three components of attitude in a desirable attitude toward dietary management actions in outpatient haemodialysis patients who are in the maintenance phase of treatment. METHODS: The participants in the study included nine patients undergoing chronic maintenance haemodialysis who have received guidance related to diet and had good test results. Ethnography, by means of participant observation and semi-structured interviews, was chosen as the research method. FINDINGS: Desirable attitude of haemodialysis patients in dietary management actions was found to have a chronological progression in one of the components of attitude: propensity of behaviour. Change in behaviour was influenced by affect and cognition. At the base of the structure of attitude lay three factors: valuing cooking with seasonal ingredients and creating special meals for seasonal occasions; family draws near, shows care and gives support; and belief in information perceived to be good for the health, which was influenced by three components of attitude: affect, cognition, and propensity of behaviour, as well as culture. CONCLUSION: Participants continue to value the food culture that they grew up with, which involves their affect towards, and cognition of, dietary management.