| Title | Description of Microbacterium luteum sp. nov., Microbacterium cremeum sp. nov., and Microbacterium atlanticum sp. nov., three novel C50 carotenoid producing bacteria |
|---|---|
| Author | Fuquan Xie1,2, Siwen Niu3, Xihuang Lin4, Shengxiang Pei2, Li Jiang2, Yun Tian1, and Gaiyun Zhang2* |
| Address | 1Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, School of Life Sciences, Xiamen University, Xiamen 361102, Fujian, P. R. China, 2Key Laboratory of Marine Biogenetic Resources, Third Institute of Oceanography, Ministry of Natural Resources, Xiamen 361005, Fujian, P. R. China, 3Engineering Innovation Center for the Development and Utilization of Marine Bioresources, Third Institute of Oceanography, Ministry of Natural Resources, Xiamen 361005, Fujian, P. R. China, 4Analysis and Test Center, Third Institute of Oceanography, Ministry of Natural Resources, Xiamen 361005, Fujian, P. R. China |
| Bibliography | Journal of Microbiology, 59(10),886-897, 2021, |
| DOI | 10.1007/s12275-021-1186-5 |
| Key Words | Microbacterium, isoprenoid biosynthetic pathway, C50 carotenoids biosynthetic pathway, C50 carotenoids production, decaprenoxanthin, sarcinaxanthin |
| Abstract | We have identified three Microbacterium strains, A18JL200T, NY27T, and WY121T, that produce C50 carotenoids. Taxonomy shows they represent three novel species. These strains shared < 98.5% 16S rRNA gene sequence identity with each other and were closely related to Microbacterium aquimaris JCM 15625T, Microbacterium yannicii JCM 18959T, Microbacterium ureisolvens CFH S00084T, and Microbacterium hibisci CCTCC AB 2016180T. Digital DNA-DNA hybridization (dDDH) values and average nucleotide identity (ANI) showed differences among the three strains and from their closest relatives, with values ranging from 20.4% to 34.6% and 75.5% to 87.6%, respectively. These values are below the threshold for species discrimination. Both morphology and physiology also differed from those of phylogenetically related Microbacterium species, supporting that they are indeed novel species. These strains produce C50 carotenoids (mainly decaprenoxanthin). Among the three novel species, A18JL200T had the highest total yield in carotenoids (6.1 mg/L or 1.2 mg/g dry cell weight). Unusual dual isoprenoid biosynthetic pathways (methylerythritol phosphate and mevalonate pathways) were annotated for strain A18JL200T. In summary, we found strains of the genus Microbacterium that are potential producers of C50 carotenoids, but their genome has to be investigated further. |