Abstract
Nitrogen-replete cultures of a high maltose-releasing strain of Chlorella (3N813A) released ammonium at pH 4; no ammonium was released by a low maltose-releasing strain (NC64A). Ammonium release by 3N813A was markedly stimulated in darkness and was sustained over 48 h. Release in light was enhanced in the presence of methionine sulphoximine, an inhibitor of glutamine synthetase, but there was only a minor increase in darkness. Amino acids, in particular alanine and glutamine, increased ammonium release in light. Ammonium release in darkness was markedly decreased in the presence of acetate and inhibitors of the Krebs cycle and gluconeogenesis. It is suggested that ammonium release by high maltose-releasing strains is due to deamination and an inability to reassimilate ammonium because of a limited supply of 2-oxoglutarate. It is further suggested that the carbon skeletons of the amino acids are utilized as gluconeogenic precursors for maltose biosynthesis.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Proceedings of the Royal Society of London. Series B: Biological Sciences
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
