Title |
Genomic and physiological analysis of C50 carotenoid-producing novel Halorubrum ruber sp. nov. |
Author |
Chi Young Hwang1, Eui-Sang Cho1, Won Jong Rhee1,2,3, Eunjung Kim1,2,3, and Myung-Ji Seo1,2,3* |
Address |
1Department of Bioengineering and Nano-Bioengineering, Incheon National University, Incheon 22012, Republic of Korea, 2Division of Bioengineering, Incheon National University, Incheon 22012, Republic of Korea, 3Research Center for Bio Materials & Process Development, Incheon National University, Incheon 22012, Republic of Korea |
Bibliography |
Journal of Microbiology, 60(10),1007-1020, 2022,
|
DOI |
10.1007/s12275-022-2173-1
|
Key Words |
haloarchaea, Halorubrum, isolation, carotenoid,
bacterioruberin |
Abstract |
A novel haloarchaeal species designated as MBLA0099T was
isolated from seawater near Yeongheung Island. Cells were
Gram-negative, non-motile, red-pigmented, and rod-shaped.
They grew at 10–45°C, within pH 5.5–9.0, and between 7.5%
and 30% NaCl concentrations. Cells were able to grow without
Mg2+ and were lysed in distilled water. The size of the
whole-genome and G + C content of DNA was 3.02 Mb and
68.9 mol%, respectively. Phylogenetic analysis shows that
the strain MBLA0099T belongs to the genus Halorubrum.
The average nucleotide and amino acid identity, and in silico
DNA-DNA hybridization values were below the species delineation
threshold. Pan-genomic analysis revealed that 3.2%
of all genes present in strain MBLA0099T were unique to the
strain. The red carotenoid produced by strain MBLA0099T
was subjected to spectrometric and chromatographic analyses
and confirmed to be bacterioruberin as C50 carotenoid.
Mevalonic acid, terpenoid backbone, and carotenoid biosynthesis
pathway were annotated for strain MBLA0099T. The
C50 carotenoid production by strain MBLA0099T was also enhanced
under various stress conditions including relatively
netural pH, high oxidative and salinity conditions. Additionally,
the strain MBLA0099T-derived bacterioruberin showed
the antioxidant activity with EC50 value of 12.29 μg/ml, based
on the evaluation of DPPH free radical scavenging activity.
The present study would be the first report on the identification
of C50 carotenoid from the strain MBLA0099T representing
a novel species of the genus Halorubrum, for which
the name Halorubrum ruber sp. nov. is proposed. The typestrain
used was MBLA0099T (= KCTC 4296T = JCM 34701T). |