Ammonia Transport by Gram-Negative Bacteria
{'Code': '08070400', 'Directorate': {'Abbreviation': 'BIO', 'LongName': 'Direct For Biological Sciences'}, 'Division': {'Abbreviation': 'MCB', 'LongName': 'Div Of Molecular and Cellular Bioscience'}}
{'SignBlockName': 'M.  Paige', 'PO_EMAI': None, 'PO_PHON': None}
Ammonia is the most readily assimilated nitrogen source for                     bacterial growth.  Before adapting to utilization of                            dinitrogen or other sources of fixed nitrogen, both itrogen                     fixing and heterotrophic microorganisms avidly scavenge the                     environment for ammonia.  Under these conditions, the active,                   concentrative uptake of ammonium ion is required for the                        utilization of ammonia and for repression of nitrogen                           fixation.                                                                                                                                                       This project will study the mechanism and metabolic                             regulation of ammonium ion transport in Escherichia coli, an                    enteric bacterium, and Azotobacter vinelandii, a free-living,                   aerobic, nitrogen-fixing bacterium.  The project involves                       both biochemical and molecular genetic approaches to four                       primary objectives: 1.  To test the hypothesis that active                      NH4+ transport is catalyzed by an NH4+/K+ antiporter which                      utilizes high-energy phosphate.  2.  To select mutants of E.                    coli with defects in the structural gene for the ammonium                       transporter.  3. To deduce the primary amino acid sequence of                   the ammonium transporter from the DNA sequence of the cloned                    gene and to identify homologus sequences in the genome of                       nitrogen-fixing bacteria.  4. To describe the mechanism of                      feedback inhibition of ammonium transport by glutamine.  This                   information will be useful in the genetic design of                             nitrogren-fixing bacteria which more readily provide ammonia                    for soil enrichment. //
{'FirstName': 'Eugene', 'LastName': 'Barnes', 'PI_MID_INIT': 'M', 'PI_SUFX_NAME': 'Jr.', 'PI_FULL_NAME': 'Eugene M Barnes', 'EmailAddress': None, 'PI_PHON': None, 'NSF_ID': '000342108', 'StartDate': '01/01/1988', 'EndDate': None, 'RoleCode': 'Principal Investigator'}
{'Name': 'Baylor College of Medicine', 'CityName': 'HOUSTON', 'ZipCode': '770303411', 'PhoneNumber': '7137981297', 'StreetAddress': '1 BAYLOR PLZ', 'StreetAddress2': None, 'CountryName': 'United States', 'StateName': 'Texas', 'StateCode': 'TX', 'CONGRESSDISTRICT': '09', 'CONGRESS_DISTRICT_ORG': 'TX09', 'ORG_UEI_NUM': 'FXKMA43NTV21', 'ORG_LGL_BUS_NAME': 'BAYLOR COLLEGE OF MEDICINE', 'ORG_PRNT_UEI_NUM': 'FXKMA43NTV21'}
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[{'Code': '1144', 'Text': 'Molecular Biophysics'}, {'Code': '9120', 'Text': 'CROSS-DIRECTORATE PROGRAMS'}]
{'url': 'https://www.nsf.gov/awardsearch/download?DownloadFileName=1987&All=true', 'xml': '8715828.xml'}