Cell aggregation in Dictyostelium discoideum appears to involve the production and detection of 3':5'-cyclic AMP. Two pertinent catalytic activities have been studied in concentrates from D. discoideum purified 50- to 100-fold. They are (i) adenylate cyclase and (ii) ATP pyrophosphohydrolase. ATP pyrophosphohydrolase activity converts ATP to 5'-AMP and pyrophosphate. The presence of 5'-AMP is an absolute requirement for adenylate cyclase activity. The presence of 3':5'-cyclic AMP is an absolute requirement for ATP pyrophosphohydrolase activity. Both activations, particularly that of ATP pyrophosphohydrolase, show narrow ranges of specificity and display significant cooperativities.
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http://dx.doi.org/10.1073/pnas.70.4.1254 | DOI Listing |
Appl Environ Microbiol
July 2024
College of Marine Life Sciences, Institute of Evolution and Marine Biodiversity, MOE Key Laboratory of Evolution and Marine Biodiversity, Frontiers Science Center for Deep Ocean Multispheres and Earth System, Center for Ocean Carbon Neutrality, Ocean University of China, Qingdao, China.
Unlabelled: Flavobacteriia are the dominant and active bacteria during algal blooms and play an important role in polysaccharide degradation. However, little is known about phages infecting , especially during green tide. In this study, a novel virus, vB_TgeS_JQ, infecting Flavobacteriia was isolated from the surface water of the Golden Beach of Qingdao, China.
View Article and Find Full Text PDFACS Catal
June 2023
School of Biology, University of St Andrews, Biomedical Sciences Research Complex, St Andrews, Fife KY16 9ST, U.K.
The bifunctional enzyme phosphoribosyl-ATP pyrophosphohydrolase/phosphoribosyl-AMP cyclohydrolase (HisIE) catalyzes the second and third steps of histidine biosynthesis: pyrophosphohydrolysis of -(5-phospho-β-D-ribosyl)-ATP (PRATP) to -(5-phospho-β-D-ribosyl)-AMP (PRAMP) and pyrophosphate in the C-terminal HisE-like domain, and cyclohydrolysis of PRAMP to -(5'-phospho-D-ribosylformimino)-5-amino-1-(5″-phospho-D-ribosyl)-4-imidazolecarboxamide (ProFAR) in the N-terminal HisI-like domain. Here we use UV-VIS spectroscopy and LC-MS to show putative HisIE produces ProFAR from PRATP. Employing an assay to detect pyrophosphate and another to detect ProFAR, we established the pyrophosphohydrolase reaction rate is higher than the overall reaction rate.
View Article and Find Full Text PDFCrit Rev Biochem Mol Biol
December 2018
a Department of Biochemistry and Molecular Biology , Michigan State University, East Lansing , MI , USA.
Derived from an ancient ATP-hydrolyzing Rossmann-like fold protein, members of the PP-loop ATP pyrophosphatase family feature an absolutely conserved P-loop-like "SxGxDS/T" motif used for binding and presenting ATP for substrate adenylylation (AMPylation). Since the first family member was reported more than 20 years ago, numerous representatives catalyzing very diverse reactions have been characterized both functionally and structurally. The availability of more than 100 high quality structures in the protein data bank provides an excellent opportunity to gain structural insights into the generally conserved catalytic mechanism and the uniqueness of the reactions catalyzed by family members.
View Article and Find Full Text PDFBiotechnol Lett
May 2013
College of Biotechnology, Tianjin University of Science & Technology, Key Laboratory of Industrial Microbiology of Education Ministry, Tianjin 300457, China.
Histidine biosynthesis in Corynebacterium glutamicum is regulated not only by feedback inhibition by the first enzyme in the pathway, but also by repression control of the synthesis of the histidine enzymes. C. glutamicum histidine genes are located and transcribed in two unlinked loci, hisEG and hisDCB-orf1-orf2-hisHA-impA-hisFI.
View Article and Find Full Text PDFJ Mol Biol
January 2010
Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan.
Guanosine 5'-monophosphate synthetase(s) (GMPS) catalyzes the final step of the de novo synthetic pathway of purine nucleotides. GMPS consists of two functional units that are present as domains or subunits: glutamine amidotransferase (GATase) and ATP pyrophosphatase (ATPPase). GATase hydrolyzes glutamine to yield glutamate and ammonia, while ATPPase utilizes ammonia to convert adenyl xanthosine 5'-monophosphate (adenyl-XMP) into guanosine 5'-monophosphate.
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