alexa Relationships Between Proton Extrusion and Fluxes of Ammonium Ions and Organic Acids in Penicillium cyclopium
Chemical Engineering

Chemical Engineering

Journal of Advanced Chemical Engineering

Author(s): N S Bolan, J Elliott, P E H Gregg

Abstract Share this page

Acidification observed in cultures of Penicillium cyclopium was mostly due to the extrusion of protons into the medium. In the absence of NH,+ , protons were extruded together with citrate. The citric acid thus produced underwent a dynamic equilibrium of continuous efflux and uptake, which was shifted towards the latter at decreasing glucose concentrations. In cultures supplied with NH,+ and glucose a stoichiometric coupling of H+ excretion with NH,+ uptake was observed. If the protons excreted were not absorbed by external buffers (e.g. tartrate ions), the pH of the medium dropped to below 2, thereby exceeding the capacity of the cells to maintain their internal pH. The decrease of intracellular pH was accompanied by the cessation of NH,+ uptake, H+ extrusion and growth. In the presence of tartrate ions the NH,+/H+ exchange proceeded until the glucose concentration of the medium dropped below 25 mM. Here, the external pH was kept above 3, without seriously affecting the intracellular pH. After termination of H+ extrusion an appreciable amount of NH,+ was taken up together with hydrogentartrate anions, thereby causing a further acidification of the medium, which was finally reversed due to the uptake of tartaric acid in the late phase of growth.

This article was published in Journal of General Microbiology and referenced in Journal of Advanced Chemical Engineering

Relevant Expert PPTs

Relevant Speaker PPTs

Recommended Conferences

Peer Reviewed Journals
 
Make the best use of Scientific Research and information from our 700 + peer reviewed, Open Access Journals
International Conferences 2017-18
 
Meet Inspiring Speakers and Experts at our 3000+ Global Annual Meetings

Contact Us

Agri, Food, Aqua and Veterinary Science Journals

Dr. Krish

[email protected]

1-702-714-7001 Extn: 9040

Clinical and Biochemistry Journals

Datta A

[email protected]

1-702-714-7001Extn: 9037

Business & Management Journals

Ronald

[email protected]

1-702-714-7001Extn: 9042

Chemical Engineering and Chemistry Journals

Gabriel Shaw

[email protected]

1-702-714-7001 Extn: 9040

Earth & Environmental Sciences

Katie Wilson

[email protected]

1-702-714-7001Extn: 9042

Engineering Journals

James Franklin

[email protected]

1-702-714-7001Extn: 9042

General Science and Health care Journals

Andrea Jason

[email protected]

1-702-714-7001Extn: 9043

Genetics and Molecular Biology Journals

Anna Melissa

[email protected]

1-702-714-7001 Extn: 9006

Immunology & Microbiology Journals

David Gorantl

[email protected]

1-702-714-7001Extn: 9014

Informatics Journals

Stephanie Skinner

[email protected]

1-702-714-7001Extn: 9039

Material Sciences Journals

Rachle Green

[email protected]

1-702-714-7001Extn: 9039

Mathematics and Physics Journals

Jim Willison

[email protected]

1-702-714-7001 Extn: 9042

Medical Journals

Nimmi Anna

[email protected]

1-702-714-7001 Extn: 9038

Neuroscience & Psychology Journals

Nathan T

[email protected]

1-702-714-7001Extn: 9041

Pharmaceutical Sciences Journals

John Behannon

[email protected]

1-702-714-7001Extn: 9007

Social & Political Science Journals

Steve Harry

[email protected]

1-702-714-7001 Extn: 9042

 
© 2008-2017 OMICS International - Open Access Publisher. Best viewed in Mozilla Firefox | Google Chrome | Above IE 7.0 version
adwords