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Generation of Marked and Markerless Mutants in Model Cyanobacterial Species
Published on: May 29, 2016
An uncultivated crenarchaeota contains functional bacteriochlorophyll a synthase
Jun Meng1, Fengping Wang, Feng Wang
1School of Life Sciences, Xiamen University, Xiamen, Fujian, PR China.
The ISME Journal
|October 3, 2008
Summary
Researchers discovered a functional enzyme for bacteriochlorophyll a synthesis in Archaea, challenging previous assumptions about this domain
Area of Science:
- Microbiology
- Biochemistry
- Molecular Biology
Background:
- The domain Archaea was not known to possess genes for bacteriochlorophyll synthesis.
- Bacteriochlorophylls are pigments involved in photosynthesis, typically found in bacteria.
Purpose of the Study:
- To investigate the presence and function of bacteriochlorophyll a synthase (bchG) in Archaea.
- To characterize a novel archaeal bchG enzyme.
Main Methods:
- Screening a metagenomic library from Pearl River sediment.
- Sequence analysis of fosmid clone 37F10.
- Cloning and heterologous expression of the putative archaeal bchG (ar-bchG) in Escherichia coli.
- Biochemical assays to confirm enzyme activity.
- Phylogenetic analysis of the ar-bchG gene.
Main Results:
- A fosmid clone (37F10) containing an archaeal 16S rRNA gene from the Miscellaneous Crenarchaeotal Group (MCG) was identified.
- An open reading frame (orf11) within the clone encoded a putative bacteriochlorophyll a synthase (bchG).
- The heterologously expressed archaeal bchG (ar-bchG) demonstrated the ability to synthesize bacteriochlorophyll a.
- Phylogenetic analysis placed ar-bchG as an ancient lineage predating bacterial bchGs.
Conclusions:
- This study provides the first evidence for a functional bacteriochlorophyll a biosynthesis enzyme in Archaea.
- The discovery challenges the long-held belief that Archaea lack photosynthetic pigment synthesis pathways.
- The findings suggest a deeper evolutionary history of bacteriochlorophyll biosynthesis than previously understood.
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