1
|
Xi H, Nie X, Gao F, Liang X, Li H, Zhou H, Cai Y, Yang C. A bacterial spermidine biosynthetic pathway via carboxyaminopropylagmatine. SCIENCE ADVANCES 2023; 9:eadj9075. [PMID: 37878710 PMCID: PMC10599626 DOI: 10.1126/sciadv.adj9075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2023] [Accepted: 09/22/2023] [Indexed: 10/27/2023]
Abstract
Spermidine, a ubiquitous polyamine, is known to be required for critical physiological functions in bacteria. Two principal pathways are known for spermidine biosynthesis, both of which involve aminopropylation of putrescine. Here, we identified a spermidine biosynthetic pathway via a previously unknown metabolite, carboxyaminopropylagmatine (CAPA), in a model cyanobacterium Synechocystis sp. PCC 6803 through an approach combining 13C and 15N tracers, metabolomics, and genetic and biochemical characterization. The CAPA pathway starts with reductive condensation of agmatine and l-aspartate-β-semialdehyde into CAPA by a previously unknown CAPA dehydrogenase, followed by decarboxylation of CAPA to form aminopropylagmatine, and ends with conversion of aminopropylagmatine to spermidine by an aminopropylagmatine ureohydrolase. Thus, the pathway does not involve putrescine and depends on l-aspartate-β-semialdehyde as the aminopropyl group donor. Genomic, biochemical, and metagenomic analyses showed that the CAPA-pathway genes are widespread in 15 different phyla of bacteria distributed in marine, freshwater, and other ecosystems.
Collapse
Affiliation(s)
- Huachao Xi
- CAS-Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Xiaoqun Nie
- CAS-Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
| | - Fang Gao
- CAS-Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
| | - Xinxin Liang
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Jiangsu, China
| | - Hu Li
- CAS-Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Haiyan Zhou
- CAS-Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Yujie Cai
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Jiangsu, China
| | - Chen Yang
- CAS-Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
| |
Collapse
|
2
|
Liang X, Deng H, Bai Y, Fan TP, Zheng X, Cai Y. Highly efficient biosynthesis of spermidine from L-homoserine and putrescine using an engineered Escherichia coli with NADPH self-sufficient system. Appl Microbiol Biotechnol 2022; 106:5479-5493. [PMID: 35931895 DOI: 10.1007/s00253-022-12110-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Revised: 07/21/2022] [Accepted: 07/27/2022] [Indexed: 11/30/2022]
Abstract
Spermidine is an important polyamine that can be used for the synthesis of various bioactive compounds in the food and pharmaceutical fields. In this study, a novel efficient whole-cell biocatalytic method with an NADPH self-sufficient cycle for spermidine biosynthesis was designed and constructed by co-expressing homoserine dehydrogenase (HSD), carboxyspermidine dehydrogenase (CASDH), and carboxyspermidine decarboxylase (CASDC). First, the enzyme-substrate coupled cofactor regeneration system from co-expression of NADP+-dependent ScHSD and NADPH-dependent AfCASDH exactly provides an efficient method for cofactor cycling. Second, we identified and characterized a putative CASDC with high decarboxylase activity from Butyrivibrio crossotus DSM 2876; it showed an optimum temperature of 35 °C and an optimum pH of 7.0, which make it better suited for the designed synthetic route. Subsequently, the protein expression level of each enzyme was optimized through the variation of the gene copy number, and a whole-cell catalyst with high catalytic efficiency was constructed successfully. Finally, a yield of 28.6 mM of spermidine was produced in a 1-L scale of E. coli whole-cell catalytic system with a 95.3% molar conversion rate after optimization of temperature, the ratio of catalyst-to-substrate, and the amount of NADP+, and a productivity of 0.17 g·L-1·h-1 was achieved. In summary, this novel pathway of constructing a whole-cell catalytic system from L-homoserine and putrescine could provide a green alternative method for the efficient synthesis of spermidine. KEY POINTS: • A novel pathway for spermidine biosynthesis was developed in Escherichia coli. • The enzyme-substrate coupled system provides an NADPH self-sufficient cycle. • Spermidine with 28.6 mM was obtained using an optimized whole-cell system.
Collapse
Affiliation(s)
- Xinxin Liang
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, Jiangsu, China
| | - Huaxiang Deng
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, Jiangsu, China
| | - Yajun Bai
- College of Life Sciences, Northwest University, Xi'an, 710069, Shanxi, China
| | - Tai-Ping Fan
- Department of Pharmacology, University of Cambridge, Cambridge, CB2 1T, UK
| | - Xiaohui Zheng
- College of Life Sciences, Northwest University, Xi'an, 710069, Shanxi, China.
| | - Yujie Cai
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, Jiangsu, China.
| |
Collapse
|