Rerouting Cellular Electron Flux To Increase the Rate of Biological Methane Production

Methanogens are anaerobic archaea that grow by producing methane, a gas that is both an efficient renewable fuel and a potent greenhouse gas. We observed that overexpression of the cytoplasmic heterodisulfide reductase enzyme HdrABC increased the rate of methane production from methanol by 30% without affecting the growth rate relative to the parent strain. Hdr enzymes are essential in all known methane-producing archaea. They function as the terminal oxidases in the methanogen electron transport system by reducing the coenzymeM(2-mercaptoethane sulfonate) and coenzyme B (7-mercaptoheptanoylthreonine sulfonate) heterodisulfide, CoM-S-S-CoB, to regenerate the thiol-coenzymes for reuse. In Methanosarcina acetivorans, HdrABC expression caused an increased rate of methanogenesis and a decrease in metabolic efficiency on methylotrophic substrates. When acetate was the sole carbon and energy source, neither deletion nor overexpression of HdrABC had an effect on growth or methane production rates. These results suggest that in cells grown on methylated substrates, the cell compensates for energy losses due to expression of HdrABC with an increased rate of substrate turnover and that HdrABC lacks the appropriate electron donor in acetate-grown cells

Rerouting Cellular Electron Flux To Increase the Rate of Biological Methane Production

Methanogens are anaerobic archaea that grow by producing methane, a gas that is both an efficient renewable fuel and a potent greenhouse gas. We observed that overexpression of the cytoplasmic heterodisulfide reductase enzyme HdrABC increased the rate of methane production from methanol by 30% without affecting the growth rate relative to the parent strain. Hdr enzymes are essential in all known methane-producing archaea. They function as the terminal oxidases in the methanogen electron transport system by reducing the coenzymeM(2-mercaptoethane sulfonate) and coenzyme B (7-mercaptoheptanoylthreonine sulfonate) heterodisulfide, CoM-S-S-CoB, to regenerate the thiol-coenzymes for reuse. In Methanosarcina acetivorans, HdrABC expression caused an increased rate of methanogenesis and a decrease in metabolic efficiency on methylotrophic substrates. When acetate was the sole carbon and energy source, neither deletion nor overexpression of HdrABC had an effect on growth or methane production rates. These results suggest that in cells grown on methylated substrates, the cell compensates for energy losses due to expression of HdrABC with an increased rate of substrate turnover and that HdrABC lacks the appropriate electron donor in acetate-grown cells

Relationship Between Neuroticism Type Of Personality Academic Procrastination In Dawan's Ethnic Students In The District Of South Central Timor

This study aims to find the relationship between neuroticism personality types and academic procrastination among ethnic Dawan students in South Central Timor Regency. This type of research is quantitative research. The population was students of the STKIP Soe with Dawan ethnicity who were taken based on predetermined criteria, while the sampling used was accidental sampling on 85 students Dawan ethnicity. Procrastination is a deliberate delay in an important task, done repeatedly on purpose and causes feelings of discomfort in a subjective way. Subjective cultural stereotypes to the East Timorese ethnic group, the people are anxious, jealous, believe in myths, and selfish. Such stereotypical traits can generally be observed in people with the neurotic personality type. Data were collected using a scale and processed and analyzed using the Pearson Product Moment correlation statistical test. The results showed that there was a significant relationship between the Neuroticism personality type and Academic Procrastination where the Pearson Coorelation value = 0.238 with a significance value of 0.029 (ƿ <0.05

Dynamic extensions of batch systems with cloud resources

Compute clusters use Portable Batch Systems (PBS) to distribute workload among individual cluster machines. To extend standard batch systems to Cloud infrastructures, a new service monitors the number of queued jobs and keeps track of the price of available resources. This meta-scheduler dynamically adapts the number of Cloud worker nodes according to the requirement profile. Two different worker node topologies are presented and tested on the Amazon EC2 Cloud service

A Critical Analysis of the Environmental Dossiers from the OECD Sponsorship Programme for the Testing of Manufactured Nanomaterials

In 2015, the OECD finally published the findings of its seven year testing programme for manufactured nanomaterials.</p