A Global approach to the hydrogen production, carnon assimilation and nitrogen metabolism of rhodobacter capsulatus by physiological and microarray analyses

Download

index.pdf

Date

2012

Author

Afşar, Nilüfer

Metadata

Show full item record

Item Usage Stats

152
views

87
downloads

One of the most important parameters affecting hydrogen production in photofermentation process is the type of carbon and nitrogen sources. For this reason in this research, the effect of different nitrogen sources (5mM ammonium chloride and 2mM glutamate) and acetate concentrations (40‐80mM) on metabolism of Rhodobacter capsulatus were investigated. First of all, physiological experiments were carried out to compare growth, hydrogen production and substrate utilization behaviors of R. capsulatus on different nitrogen sources and acetate concentrations. For further understanding of hydrogen production, carbon assimilation and nitrogen metabolism; microarray analysis were conducted. For this purpose, an Affymetrix GeneChip for R. capsulatus was custom designed and manufactured. An efficient RNA isolation protocol from R. capsulatus was optimized for use of microarray analysis. Validation of the microarray experiments and custom designed R. capsulatus were carried out by RT‐qPCR analysis. On 5mM ammonium chloride containing medium, transcription of genes related to transport, assimilation and utilization of acetate were significantly up‐regulated compared to 2mM glutamate medium. On the other hand, nitrogenase enzyme encoding genes were significantly down‐regulated on ammonium chloride containing medium. Although transcription of genes that take role in acetate assimilation did not show a significant difference on 80mM acetate compared to 40mM acetate; TCA cycle, photosynthetic apparatus, electron transport and Calvin cycle related genes were significantly down‐regulated on 80mM acetate. From microarray data analysis results, it was suggested for the first time that Rhodobacter capsulatus might assimilate acetate by using two different routes using glyoxylate cycle and/or ethylmalonyl‐CoA pathway.

Subject Keywords

Hydrogen., Carbon., Nitrogen., Fermentation., Bacteria.

URI

http://etd.lib.metu.edu.tr/upload/12615030/index.pdf
https://hdl.handle.net/11511/22074

Collections

Graduate School of Natural and Applied Sciences, Thesis

Suggestions

OpenMETU
Core

Process development for continuous photofermentative hydrogen production Boran, Efe; Eroğlu, İnci; Özgür, Ebru; Department of Chemical Engineering (2011) By the integration of dark and photo fermentative hydrogen production processes, higher yields of hydrogen can be obtained from biomass. In the first step, biomass is utilized for hydrogen production by dark fermentation and in the second step, the effluent of dark fermentation is further utilized for hydrogen production by photofermentation using photosynthetic purple non-sulfur bacteria. The purpose of this study was to develop a solar pilot scale tubular photobioreactor (PBR) for continuous photo ferment...
A density functional study on some cyclic N10 isomers Türker, Lemi (Elsevier BV, 2019-4) Polynitrogen compounds, comprising only nitrogen atoms, are rare. They are considered as promising candidates of clean (green) high energy density materials because of their high energy content and their sole decomposition product is N2. Extending the previous work which was on cyclic N8 isomers, in this study some cyclic N10 isomers having 1e4 cycles are considered within the limitations of density functional theory at the levels of B3LYP/6-311þþG(d,p) and B3LYP/cc-PVTZ. Some of the structures, includ...
A comparative study of spectrophotometric and iodometric back titration methods for hydrogen sulfide determination in anoxic basins Basturk, O; Romanov, A; Gokmen, S; Konovalov, S (2000-01-01) Iodometric Back Titration (TBT) and Spectrophotometric (SPM) methods are two common methods used in the determination of hydrogen sulfide concentrations in anoxic basins, like in the upper sections of the Black Sea anoxic waters. Although the results obtained by both methods are in agreement when the concentrations of sulfide are higher than 30 mu M/l, IBT analysis gives more reproducible results compared to SPM analysis. On the other hand, the reproducibility of the SPM is better than that of IBT method wh...
A compact tubular photobioreactor for outdoor hydrogen production from molasses KAYAHAN, Emine; Eroglu, Inci; Koku, Harun (2017-01-26) Hydrogen can be produced sustainably by photofermentation of biomass. For an economically feasible operation, the process should be implemented outdoors using low-cost organic material. In the current study, molasses from a sugar factory was utilized for photofermentative hydrogen production. The experiment was run with Rhodobacter capsulatus YO3 (hup-) in fed-batch mode under outdoor conditions in Ankara between July 12, 2015 and July 24, 2015. The stacked U-tube photobioreactor (9 L) designed for outdoor ...
Investigation Of Influencing Factors For Biological Hydrogen Production By R. Capsulatus In Tubular Photo-Bioreactors Boran, E.; Ozgur, E.; Gebicki, J.; van der Burg, J.; YÜCEL, MUSTAFA; Gündüz, Ufuk; Modigel, M.; Eroglu, I. (2009-05-13) Biological hydrogen production processes are considered as an environmentally friendly way to produce hydrogen. They offer the chance to produce hydrogen from renewable energy sources, like sunlight and biomass. This study aims the process development for a photo-fermentative hydrogen production by photosynthetic purple-non-sulfur bacteria, Rhodobacter capsulatus, in a large scale (80L) tubular photo-bioreactor, in outdoor conditions, using acetate as carbon source. It was shown that Rhodobacter capsulatus ...

Citation Formats

N. Afşar, “A Global approach to the hydrogen production, carnon assimilation and nitrogen metabolism of rhodobacter capsulatus by physiological and microarray analyses,” Ph.D. - Doctoral Program, Middle East Technical University, 2012.