title: Intracellular localization of glutamine synthetase in a nitrogen-fixing cyanobacterium Anabaena cylindrical.
abstract: The major route of ammonia assimilation is the reaction which is catalyzed by glutamine synthetase to give ammonia. Cell-free extracts and purified thylakoid membranes using differential centrifugation and density gradient techniques were assayed for the percentage activity of the enzyme. Glutamine synthetase was detected in all cell-free extracts. Seventy six percent of the enzyme activity was found associated with the thylakoid membranes. Using antiserum raised to the thylakoids, 78.5% inhibition of the enzyme activity was obtained.
authors.affiliation: Faculty of Pharmacy and Medical Sciences, Amman University, Postal Code 19328, Amman-Jordan.
authors.forename: Husni S
authors.initials: HS
authors.lastname: Farah
authors.forename: Nooman A
authors.initials: NA
authors.lastname: Khalaf
authors.forename: Ashok K
authors.initials: AK
authors.lastname: Shakya
authors.forename: Mustafa T
authors.initials: MT
authors.lastname: Ubeid
authors.forename: Anwar D
authors.initials: AD
authors.lastname: Maraqa
authors.forename: Abdul-Karim
authors.initials: AK
authors.lastname: Sallal
mesh_terms: D000641:Ammonia / Q000737:chemistry; D017033:Anabaena / Q000378:metabolism*; D001709:Biotechnology / Q000379:methods; D002474:Cell-Free System; D002499:Centrifugation, Density Gradient; D002734:Chlorophyll / Q000737:chemistry; D000458:Cyanobacteria / Q000378:metabolism*; D005974:Glutamate-Ammonia Ligase / Q000096:biosynthesis* / Q000737:chemistry; D009584:Nitrogen / Q000737:chemistry*; D013395:Sucrose / Q000494:pharmacology; D020524:Thylakoids / Q000737:chemistry / Q000378:metabolism
chemical_list: D002734:Chlorophyll; D013395:Sucrose; D000641:Ammonia; D005974:Glutamate-Ammonia Ligase; D009584:Nitrogen