Heterologous production of thermophile Thermochromatium tepidum photosynthetic reaction centre and light harvesting 1 complexes in the mesophile Rhodobacter sphaeroides and thermal stabilities of a hybrid core complex.

Heterologous production of thermophile Thermochromatium tepidum photosynthetic reaction centre and light harvesting 1 complexes in the mesophile Rhodobacter sphaeroides and thermal stabilities of a hybrid core complex. Appl Environ Microbiol. 2017 Aug 18;: Authors: Jun D, Huang V, Beatty JT Abstract The photosynthetic complexes of the thermophile Thermochromatium tepidum are of considerable interest in biohybrid solar cell applications because of the capability of thermophilic proteins to tolerate elevated temperatures. Synthetic operons encoding reaction centre (RC) and light harvesting 1 (LH1) pigment-protein complexes of T. tepidum were expressed in the mesophile Rhodobacter sphaeroides The T. tepidum RC (TRC) was assembled, and functional with the addition of menadione to populate the QA pocket. The production of the T. tepidum LH1 (TLH1) was increased by selection of a phototrophy-capable mutant after UV irradiation mutagenesis, which yielded a hybrid RC-TLH1 core complex consisting of the R. sphaeroides RC and T. tepidum TLH1, confirmed by the absorbance peak of TLH1 at 915 nm. Affinity chromatography partial purification and subsequent sucrose gradient analysis of the hybrid RC-TLH1 core complex indicated that this core complex assembled as a monomer. Furthermore, the RC-TLH1 hybrid core complex was more tolerant of 70 °C temperature than the R. sphaeroides RC-LH1 core complexes in both the dimeric and monomeric forms: after ...
Source: Applied and Environmental Microbiology - Category: Microbiology Authors: Tags: Appl Environ Microbiol Source Type: research