ハラグチ　ユウジ   HARAGUCHI Yuuji   原口　裕次    所属   医学研究科 医学研究科 (医学部医学科をご参照ください)    職種   特任准教授
論文種別	原著
言語種別	英語
査読の有無	査読あり
表題	Photosynthetic production of glutamine through metabolic analysis-based engineering of Picosynechococcus sp. PCC 7002.
掲載誌名	正式名：Metabolic engineering communications 略　 称：Metab Eng Commun ISSNコード：22140301/22140301
掲載区分	国外
出版社	Elsevier
巻・号・頁	23,pp.e00284
総ページ数	9
著者・共著者	KATO Yuichi, TSUJI Ayaka, HARAGUCHI Yuji, SHIMIZU Tatsuya, KONDO Akihiko, HASUNUMA Tomohisa
発行年月	2026/06
概要	Glutamine is an important nitrogen donor in the biosynthesis of nucleotides and several other amino acids. Proliferating cells consume high amounts of glutamine, and cell culture media contain glutamine as the most abundant amino acid. Glutamine is industrially manufactured through bacterial fermentation, which requires external supplementation with sugars as the carbon source. Using the cyanobacterium Picosynechococcus sp. PCC 7002, this study aimed to develop a method for the photosynthetic production of glutamine using CO2 as the sole carbon source. The introduction of glutamate dehydrogenase from Corynebacterium glutamicum and glutamine synthase from Saccharomyces cerevisiae increased the concentration of extracellularly released glutamine. Metabolome analysis revealed decreased intracellular citrate levels in glutamine-producing cells. To enhance citrate replenishment, metabolic engineering approaches, including l-lactate assimilation and glycogen deficiency, were examined. The introduction of pyruvate carboxylase and citrate synthase from C. glutamicum significantly increased glutamine production. After optimizing light intensity and CO2 concentration, the recombinant strain produced 1168.5 μM (170.76 mg L-1) glutamine. This study establishes metabolic engineering approaches for converting CO2 into glutamine and demonstrates that cyanobacteria are promising photosynthetic producers of glutamine.
DOI	10.1016/j.mec.2026.e00284
PMID	42376325