Cloning and heterologous expression of chlorophyll a synthase in Rhodobacter sphaeroides


Ipekoglu E. M., Gocmen K., Oz M. T., Gurgan M., Yucel M.

JOURNAL OF BASIC MICROBIOLOGY, cilt.57, sa.3, ss.238-244, 2017 (SCI-Expanded) identifier identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 57 Sayı: 3
  • Basım Tarihi: 2017
  • Doi Numarası: 10.1002/jobm.201600580
  • Dergi Adı: JOURNAL OF BASIC MICROBIOLOGY
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.238-244
  • Anahtar Kelimeler: Chlorophyll a synthase, hydrogen production, photosynthesis, Prochlorococcus marinus, Rhodobacter sphaeroides, PHOTOSYNTHETIC CARBON ASSIMILATION, HYDROGEN-PRODUCTION, GENOME SEQUENCE, LIGHT-INTENSITY, C-3 PLANTS, BIOSYNTHESIS, BACTERIOCHLOROPHYLL, EVOLUTION, YIELD
  • Orta Doğu Teknik Üniversitesi Adresli: Evet

Özet

Rhodobacter sphaeroides is a purple non-sulfur bacterium which photoheterotrophically produces hydrogen from organic acids under anaerobic conditions. A gene coding for putative chlorophyll a synthase (chlG) from cyanobacterium Prochlorococcus marinus was amplified by nested polymerase chain reaction and cloned into an inducible-expression plasmid which was subsequently transferred to R. sphaeroides for heterologous expression. Induced expression of chlG in R. sphaeroides led to changes in light absorption spectrum within 400-700nm. The hydrogen production capacity of the mutant strain was evaluated on hydrogen production medium with 15mM malate and 2mM glutamate. Hydrogen yield and productivity were increased by 13.6 and 22.6%, respectively, compared to the wild type strain. The results demonstrated the feasibility of genetic engineering to combine chlorophyll and bacteriochlorophyll biosynthetic pathways which utilize common intermediates. Heterologous expression of key enzymes from biosynthetic pathways of various pigments is proposed here as a general strategy to improve absorption spectra and yield of photosynthesis and hydrogen gas production in bacteria.