Biomaterial Database

The effect of groES on the groEL-dependent assembly of dodecameric glutamine synthetase in the presence of ATP and ADP. 1994

M T Fisher

Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City 66160-7421.

The yields of active dodecameric glutamine synthetase (GS) are significantly increased when in vitro folding is initiated in the presence of the Escherichia coli groE chaperonins and ATP (37 degrees C). To observe the effects of chaperonins and ATP on GS assembly, the GS assembly intermediates were separated by nondenaturing gel electrophoresis, visualized by Western analysis, and studied as a function of time. The form of GS that was initially released from groEL is monomeric. After the monomers formed dimers, active GS oligomers were assembled by the association of assembly competent dimers with higher order even-numbered oligomers until the dodecamer was formed. When ATP was added to the groEL.GS complex (no groES), a groEL.GS complex remained visible for up to 30 min after the renaturation was initiated. This slow disappearance of the groEL.GS complex is consistent with observed lags in both the GS activity regain profile and the assembly-dependent increase in GS tryptophan fluorescence. When groES was present, the addition of ATP resulted in the disappearance of observable complex at early sample times (< 2 min). Concomitantly, the rates of the regain of GS activity and the GS-dependent increase in tryptophan fluorescence intensity showed substantial accelerations. These results indicate that groES facilitates GS assembly from groEL by inducing the rapid release of GS from groEL, which in turn increases the concentration of assembly competent GS monomers. In addition, groES can initiate renaturation of GS from the groEL.GS arrested complex in the presence of ADP. When chaperonin-dependent GS renaturation was initiated with ATP or ADP (> or = 2 mM), the rates were identical. Since ATP hydrolysis is not absolutely required, the combined binding energies of groES and ATP (or ADP) appear to be sufficient to weaken the binding affinity of groEL for GS subunits and facilitate the release and refolding of assembly competent GS monomers from groEL.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D004926	Escherichia coli	A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.	Alkalescens-Dispar Group,Bacillus coli,Bacterium coli,Bacterium coli commune,Diffusely Adherent Escherichia coli,E coli,EAggEC,Enteroaggregative Escherichia coli,Enterococcus coli,Diffusely Adherent E. coli,Enteroaggregative E. coli,Enteroinvasive E. coli,Enteroinvasive Escherichia coli
D005974	Glutamate-Ammonia Ligase	An enzyme that catalyzes the conversion of ATP, L-glutamate, and NH3 to ADP, orthophosphate, and L-glutamine. It also acts more slowly on 4-methylene-L-glutamate. (From Enzyme Nomenclature, 1992) EC 6.3.1.2.	Glutamine Synthetase,Glutamate Ammonia Ligase (ADP),Glutamate Ammonia Ligase,Ligase, Glutamate-Ammonia,Synthetase, Glutamine
D006360	Heat-Shock Proteins	Proteins which are synthesized in eukaryotic organisms and bacteria in response to hyperthermia and other environmental stresses. They increase thermal tolerance and perform functions essential to cell survival under these conditions.	Stress Protein,Stress Proteins,Heat-Shock Protein,Heat Shock Protein,Heat Shock Proteins,Protein, Stress
D000244	Adenosine Diphosphate	Adenosine 5'-(trihydrogen diphosphate). An adenine nucleotide containing two phosphate groups esterified to the sugar moiety at the 5'-position.	ADP,Adenosine Pyrophosphate,Magnesium ADP,MgADP,Adenosine 5'-Pyrophosphate,5'-Pyrophosphate, Adenosine,ADP, Magnesium,Adenosine 5' Pyrophosphate,Diphosphate, Adenosine,Pyrophosphate, Adenosine
D000255	Adenosine Triphosphate	An adenine nucleotide containing three phosphate groups esterified to the sugar moiety. In addition to its crucial roles in metabolism adenosine triphosphate is a neurotransmitter.	ATP,Adenosine Triphosphate, Calcium Salt,Adenosine Triphosphate, Chromium Salt,Adenosine Triphosphate, Magnesium Salt,Adenosine Triphosphate, Manganese Salt,Adenylpyrophosphate,CaATP,CrATP,Manganese Adenosine Triphosphate,MgATP,MnATP,ATP-MgCl2,Adenosine Triphosphate, Chromium Ammonium Salt,Adenosine Triphosphate, Magnesium Chloride,Atriphos,Chromium Adenosine Triphosphate,Cr(H2O)4 ATP,Magnesium Adenosine Triphosphate,Striadyne,ATP MgCl2
D001426	Bacterial Proteins	Proteins found in any species of bacterium.	Bacterial Gene Products,Bacterial Gene Proteins,Gene Products, Bacterial,Bacterial Gene Product,Bacterial Gene Protein,Bacterial Protein,Gene Product, Bacterial,Gene Protein, Bacterial,Gene Proteins, Bacterial,Protein, Bacterial,Proteins, Bacterial
D017510	Protein Folding	Processes involved in the formation of TERTIARY PROTEIN STRUCTURE.	Protein Folding, Globular,Folding, Globular Protein,Folding, Protein,Foldings, Globular Protein,Foldings, Protein,Globular Protein Folding,Globular Protein Foldings,Protein Foldings,Protein Foldings, Globular
D018834	Chaperonin 60	A group I chaperonin protein that forms the barrel-like structure of the chaperonin complex. It is an oligomeric protein with a distinctive structure of fourteen subunits, arranged in two rings of seven subunits each. The protein was originally studied in BACTERIA where it is commonly referred to as GroEL protein.	Heat-Shock Proteins 60,hsp60 Family,GroEL Protein,GroEL Stress Protein,Heat-Shock Protein 60,hsp60 Protein,Heat Shock Protein 60,Heat Shock Proteins 60
D018835	Chaperonin 10	A group I chaperonin protein that forms a lid-like structure which encloses the non-polar cavity of the chaperonin complex. The protein was originally studied in BACTERIA where it is commonly referred to as GroES protein.	Heat-Shock Proteins 10,hsp10 Family,GroES Protein,GroES Stress Protein,Heat-Shock Protein 10,hsp10 Protein,Heat Shock Protein 10,Heat Shock Proteins 10