Carotenoid productivity in human intestinal bacteria Eubacterium limosum and Leuconostoc mesenteroides with functional analysis of their carotenoid biosynthesis genes  

作　　者：Wataru Matsumoto Miho Takemura Haruka Nanaura Yuta Ami Takashi Maoka Kazutoshi Shindo Shin Kurihara Norihiko Misawa 

机构地区：[1]Research Institute for Bioresources and Biotechnology,Ishikawa Prefectural University,1-308,Suematsu,Nonoich-shi 921-8836,Japan [2]Department of Science and Technology on Food Safety,Kinki University,930 Nishimitani,Kinokawa,Wakayama 649-6493,Japan [3]Research Institute for Production Development,Shimogamo-morimotocho,Sakyo-ku,Kyoto 606-0805,Japan [4]Department of Food and Nutrition,Japan Women’s University,Mejirodai,Bunkyo-ku,Tokyo 112-8681,Japan

出　　处：《Engineering Microbiology》2024年第2期1-11,共11页工程微生物学（英文）

摘　　要：The human intestinal microbiota that comprise over 1,000 species thrive in dark and anaerobic environments.They are recognized for the production of diverse low-molecular-weight metabolites crucial to human health and diseases.Carotenoids,low-molecular-weight pigments known for their antioxidative activity,are delivered to humans through oral intake.However,it remains unclear whether human intestinal bacteria biosynthesize carotenoids as part of the in-situ microbiota.In this study,we investigated carotenoid synthesis genes in vari-ous human gut and probiotic bacteria.As a result,novel candidates,the crtM and crtN genes,were identified in the carbon monoxide-utilizing gut anaerobe Eubacterium limosum and the lactic acid bacterium Leuconostoc mesenteroides subsp.mesenteroides.These gene candidates were isolated,introduced into Escherichia coli,which synthesized a carotenoid substrate,and cultured aerobically.Structural analysis of the resulting carotenoids re-vealed that the crtM and crtN gene candidates of E.limosum and L.mesenteroides mediate the production of 4,4′-diaponeurosporene through 15-cis-4,4′-diapophytoene.Evaluation of the crtE-homologous genes in these bacteria indicated their non-functionality for C40-carotenoid production.E.limosum and L.mesenteroides,along with the known carotenogenic lactic acid bacterium Lactiplantibacillus plantarum,were observed to produce no carotenoids under strictly anaerobic conditions.The two lactic acid bacteria synthesized detectable levels of 4,4′-diaponeurosporene under semi-aerobic conditions.The findings highlight that the obligate anaerobe E.limo-sum retains aerobically functional C30-carotenoid biosynthesis genes,potentially with no immediate self-utility,suggesting an evolutionary direction in carotenoid biosynthesis.(229 words)

关 键 词：C_(30)carotenoid biosynthesis Obligate anaerobe Human gut bacterium Eubacterium limosum Leuconostoc mesenteroides Lactiplantibacillus plantarum 

分 类 号：Q93[生物学—微生物学]