Hydrogen production by using Rhodobacter capsulatus mutants with genetically modified electron transfer chains


Ozturk Y., Yucel M., Daldal F., Mandaci S., Gunduz U., Turker L., ...Daha Fazla

INTERNATIONAL JOURNAL OF HYDROGEN ENERGY, cilt.31, sa.11, ss.1545-1552, 2006 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 31 Sayı: 11
  • Basım Tarihi: 2006
  • Doi Numarası: 10.1016/j.ijhydene.2006.06.042
  • Dergi Adı: INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.1545-1552
  • Anahtar Kelimeler: Rhodobacter capsulatus, electron transfer chain, Cytochromes c2/cy, Cytochromes cbb(3) oxidase, quinol oxidase, hydrogen, RegB/RegA, PHOTOSYNTHETIC BACTERIA, NITROGEN-FIXATION, CYTOCHROME C(Y), TRANSDUCTION, SYSTEM, RESPIRATION, METABOLISM, EXPRESSION, MEMBRANE
  • Orta Doğu Teknik Üniversitesi Adresli: Evet

Özet

In Rhodobacter capsulatus excess reducing equivalents generated by organic acid oxidation is consumed to reduce protons into hydrogen by the activity of nitrogenase. Nitrogenase serves as a redox-balancing tool and is activated by the RegB/RegA global regulatory system during photosynthetic growth. The terminal cytochrome cbb3 oxidase and the redox state of the cyclic photosynthetic electron transfer chain serve redox signaling to the RegB/RegA regulatory systems in Rhodobacter. In this study, hydrogen production of various R. capsulatus strains harboring the genetically modified electron carrier cytochromes or lacking the cyt cbb(3) oxidase or the quinol oxidase were compared with the wild type. The results indicated that hydrogen production of mutant strains with modified electron carrier cytochromes decreased 3- to 4-fold, but the rate of hydrogen production increased significantly in a cbb(3) mutant. Moreover, hydrogen production efficiency of various R. capsulatus strains further increased by inactivation of uptake hydrogenase genes. (c) 2006 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved.