Poly(lactate-co-3-hydroxybutyrate)[P(LA-co-3HB)]is a high-molecular-weight biomaterial with excellent biocompatibility and biodegradability.In this study,the properties of P(LA-co-3HB)were examined and found to be aff...Poly(lactate-co-3-hydroxybutyrate)[P(LA-co-3HB)]is a high-molecular-weight biomaterial with excellent biocompatibility and biodegradability.In this study,the properties of P(LA-co-3HB)were examined and found to be affected by its lactate fraction.The efficiency of lactyl-CoA biosynthesis from intracellular lactate significantly affected the microbial synthesis of P(LA-co-3HB).Two CoA transferases from Anaerotignum lactatifermentans and Bacillota bacterium were selected for use in copolymer biosynthesis from 11 candidates.We found that cotAl enhanced the lactate fraction by 31.56%compared to that of the frequently used modified form of propionyl-CoA transferase from Anaerotignum propionicum.In addition,utilizing xylose as a favorable carbon source and blocking the lactate degradation pathway further enhanced the lactate fraction to 30.42 mol%and 52.84 mol%,respectively.Furthermore,when a 5 L bioreactor was used for fermentation utilizing xylose as a carbon source,the engineered strain produced 60.60 wt%P(46.40 mol%LA-co-3HB),which was similar to the results of our flask experiments.Our results indicate that the application of new CoA transferases has great potential for the biosynthesis of other lactate-based copolymers.展开更多
Poly(3-hydroxybutyrate-co-lactate)[P(3HB-co-LA)]is a highly promising valuable biodegradable material with good biocompatibility and degradability.Vibrio natriegens,owing to its fast-growth,wide substrate spectrum cha...Poly(3-hydroxybutyrate-co-lactate)[P(3HB-co-LA)]is a highly promising valuable biodegradable material with good biocompatibility and degradability.Vibrio natriegens,owing to its fast-growth,wide substrate spectrum characteristics,was selected to produce P(3HB-co-LA).Herein,the crucial role of acetyltransferase PN96-18060 for PHB synthesis in V.natriegens was identified.Heterologous pathway of P(3HB-co-LA)was introduced into V.natriegens successfully,in addition,overexpression of the dldh gene led to 1.84 fold enhancement of the lactate content in P(3HB-co-LA).Finally,the production of P(3HB-co-LA)was characterized under different carbon sources.The lactate fraction in P(3HB-co-LA)was increased to 28.3 mol%by the modification,about 1.84 times of that of the control.This is the first successful case of producing the P(3HB-co-LA)in V.natriegens.Collectively,this study showed that V.natriegens is an attractive host organism for producing P(3HB-co-LA)and has great potential to produce other co-polymers.展开更多
基金supported by the National Natural Science Foundation of China(22278137)the National Key R&D Program of China(2021YFC2103500)Partially supported by Open Funding Project of the State Key Laboratory of Bioreactor Engineering.
文摘Poly(lactate-co-3-hydroxybutyrate)[P(LA-co-3HB)]is a high-molecular-weight biomaterial with excellent biocompatibility and biodegradability.In this study,the properties of P(LA-co-3HB)were examined and found to be affected by its lactate fraction.The efficiency of lactyl-CoA biosynthesis from intracellular lactate significantly affected the microbial synthesis of P(LA-co-3HB).Two CoA transferases from Anaerotignum lactatifermentans and Bacillota bacterium were selected for use in copolymer biosynthesis from 11 candidates.We found that cotAl enhanced the lactate fraction by 31.56%compared to that of the frequently used modified form of propionyl-CoA transferase from Anaerotignum propionicum.In addition,utilizing xylose as a favorable carbon source and blocking the lactate degradation pathway further enhanced the lactate fraction to 30.42 mol%and 52.84 mol%,respectively.Furthermore,when a 5 L bioreactor was used for fermentation utilizing xylose as a carbon source,the engineered strain produced 60.60 wt%P(46.40 mol%LA-co-3HB),which was similar to the results of our flask experiments.Our results indicate that the application of new CoA transferases has great potential for the biosynthesis of other lactate-based copolymers.
基金supported by the National Natural Science Foundation of China(22278137)the National Key R&D Program of China(2021YFC2103500)Partially supported by Open Funding Project of the State Key Laboratory of Bioreactor Engineering.
文摘Poly(3-hydroxybutyrate-co-lactate)[P(3HB-co-LA)]is a highly promising valuable biodegradable material with good biocompatibility and degradability.Vibrio natriegens,owing to its fast-growth,wide substrate spectrum characteristics,was selected to produce P(3HB-co-LA).Herein,the crucial role of acetyltransferase PN96-18060 for PHB synthesis in V.natriegens was identified.Heterologous pathway of P(3HB-co-LA)was introduced into V.natriegens successfully,in addition,overexpression of the dldh gene led to 1.84 fold enhancement of the lactate content in P(3HB-co-LA).Finally,the production of P(3HB-co-LA)was characterized under different carbon sources.The lactate fraction in P(3HB-co-LA)was increased to 28.3 mol%by the modification,about 1.84 times of that of the control.This is the first successful case of producing the P(3HB-co-LA)in V.natriegens.Collectively,this study showed that V.natriegens is an attractive host organism for producing P(3HB-co-LA)and has great potential to produce other co-polymers.
