biostudies-literatureEsquivel-Elizondo SDeutsche ForschungsgemeinschaftAlexander von Humboldt-Stiftung594524https://www.ebi.ac.uk/biostudies/studies/S-EPMC7873966biostudies-literatureUnknown11Bulk production of medium-chain carboxylates (MCCs) with 6-12 carbon atoms is of great interest to biotechnology. Open cultures (e.g., reactor microbiomes) have been utilized to generate MCCs in bioreactors. When in-line MCC extraction and prevention of product inhibition is required, the bioreactors have been operated at mildly acidic pH (5.0-5.5). However, model chain-elongating bacteria grow optimally at neutral pH values. Here, we isolated a chain-elongating bacterium (strain 7D4C2) that grows at mildly acidic pH. We studied its metabolism and compared its whole genome and the reverse β-oxidation (rBOX) genes to other bacteria. Strain 7D4C2 produces lactate, acetate, <i>n</i>-butyrate, <i>n</i>-caproate, biomass, and H₂/CO₂ from hexoses. With only fructose as subsFrontiers in microbiologyThe Isolate <i>Caproiciproducens</i> sp. 7D4C2 Produces <i>n</i>-Caproate at Mildly Acidic Conditions From Hexoses: Genome and rBOX Comparison With Related Strains and Chain-Elongating Bacteria.PMC7873966EXC 2124 – 390838134HU 566/12-1Jeon BSBessarab IEsquivel-Elizondo SHuson DHBagcı CAngenent LTWilliams RBHTemovska MfalseThe Isolate <i>Caproiciproducens</i> sp. 7D4C2 Produces <i>n</i>-Caproate at Mildly Acidic Conditions From Hexoses: Genome and rBOX Comparison With Related Strains and Chain-Elongating Bacteria.Bulk production of medium-chain carboxylates (MCCs) with 6-12 carbon atoms is of great interest to biotechnology. Open cultures (e.g., reactor microbiomes) have been utilized to generate MCCs in bioreactors. When in-line MCC extraction and prevention of product inhibition is required, the bioreactors have been operated at mildly acidic pH (5.0-5.5). However, model chain-elongating bacteria grow optimally at neutral pH values. Here, we isolated a chain-elongating bacterium (strain 7D4C2) that grows at mildly acidic pH. We studied its metabolism and compared its whole genome and the reverse β-oxidation (rBOX) genes to other bacteria. Strain 7D4C2 produces lactate, acetate, <i>n</i>-butyrate, <i>n</i>-caproate, biomass, and H₂/CO₂ from hexoses. With only fructose as subs2020-01-01T00:00:00Z20202026-05-02T13:18:39.749Z2021-02-21T10:44:09ZS-EPMC78739663358456310.3389/fmicb.2020.594524