{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/20009"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/20009","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Genetic and biochemical analysis of the colicin I receptor gene of Escherichia coli: Structural organization and transcriptional control mechanisms","abstract":"The cir gene, which encodes the colicin I receptor protein, is one of several outer membrane proteins synthesized by Escherichia coli in response to iron limitation. The location, organization, and regulation of cir and its neighboring genes were examined by a molecular genetic approach. Following cloning of the cir region, physical mapping and complementation analysis established the position of cir between mgl and nfo on the E. coli chromosome. A gene encoding a 32,000-dalton protein was located downstream of and adjacent to cir, was not part of the same transcriptional unit, and was not regulated by iron. The Cir protein was processed by removal of a signal peptide and the mature form had an amino terminal sequence which closely resembled that of other TonB-dependent proteins.","abstract_html":"The cir gene, which encodes the colicin I receptor protein, is one of several outer membrane proteins synthesized by Escherichia coli in response to iron limitation. The location, organization, and regulation of cir and its neighboring genes were examined by a molecular genetic approach. Following cloning of the cir region, physical mapping and complementation analysis established the position of cir between mgl and nfo on the E. coli chromosome. A gene encoding a 32,000-dalton protein was located downstream of and adjacent to cir, was not part of the same transcriptional unit, and was not regulated by iron. The Cir protein was processed by removal of a signal peptide and the mature form had an amino terminal sequence which closely resembled that of other TonB-dependent proteins.","abstract_has_math":false,"creators":["Griggs, David William"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"Ph.D.","degree_level":"Dissertation","degree_discipline":"Microbiology","degree_department":null,"school":null,"contributors":["Konisky, Jordan"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2011,"date_issued":"2011-05-07T12:25:54Z","date_published":"2011-05-07T12:25:54Z","updated_at":"2026-07-22T22:25:15Z","subjects":["Biology, Molecular","Biology, Microbiology"],"languages":["eng"],"rights":["Copyright 1989 Griggs, David William"],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["AAI8916254","(UMI)AAI8916254"],"render_values":[{"text":"AAI8916254","href":null,"code":true},{"text":"(UMI)AAI8916254","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/2142/20009","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Konisky, Jordan"]},{"key":"dc:creator","label":"Author","values":["Griggs, David William"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2011-05-07T12:25:54Z","10000-01-01","1989"]},{"key":"dc:type","label":"Dc Type","values":["text"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Microbiology"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Dissertation"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Ph.D."]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["University of Illinois at Urbana-Champaign"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Biology, Molecular","Biology, Microbiology"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["eng"]},{"key":"dc:rights","label":"Dc Rights","values":["Copyright 1989 Griggs, David William"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["AAI8916254","(UMI)AAI8916254","http://hdl.handle.net/2142/20009"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["The cir gene, which encodes the colicin I receptor protein, is one of several outer membrane proteins synthesized by Escherichia coli in response to iron limitation. The location, organization, and regulation of cir and its neighboring genes were examined by a molecular genetic approach. Following cloning of the cir region, physical mapping and complementation analysis established the position of cir between mgl and nfo on the E. coli chromosome. A gene encoding a 32,000-dalton protein was located downstream of and adjacent to cir, was not part of the same transcriptional unit, and was not regulated by iron. The Cir protein was processed by removal of a signal peptide and the mature form had an amino terminal sequence which closely resembled that of other TonB-dependent proteins.","The molecular basis for iron-regulated expression of cir was investigated by genetic and biochemical means. Deletion analysis of the cloned promoter region allowed delineation of sequences necessary for control of transcription initiating at the two promoters P1 and P2. Gel retardation assays were used to demonstrate a highly specific interaction between purified Fur (ferric uptake regulation) protein and the iron control region. An operator sequence spanning 43-47 base pairs and completely encompassing the two promoters was identified by DNase I protection experiments, with binding occurring in a metal-dependent fashion. Thus, during iron replete growth, Fur appears to act as a repressor of transcription by blocking formation of a DNA-RNA polymerase complex. Expression of cir in an miaA mutant was comparable to that in a wild type strain, so no ancillary role in iron-regulation based on the modification of the affected tRNA species was detected. Characterized and putative Fur recognition sites from several genes were analyzed and classified by statistical methods.","In both high- and low-iron media, functional Crp protein and cyclic adenosine 3$\\sp\\prime$,5$\\sp\\prime$-monophosphate (cAMP) were required for maximal production of the receptor. A potential cAMP-CRP binding site located in the long leader region between the cir promoters and the start of the protein-coding region was suggested by sequence and mutational analysis.","Made available in DSpace on 2011-05-07T12:25:54Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 8916254.pdf: 4456928 bytes, checksum: b0883c8acab5481d85aab06001cae5f3 (MD5) Previous issue date: 1989","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T14:40:56Z Item is restricted indefinitely.","Restriction data tranferred 2014-07-01T11:17:38-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: ETDs are only available to UIUC Users without author permission","ETDs are only available to UIUC Users without author permission","U of I Only"]},{"key":"dc:title","label":"Title","values":["Genetic and biochemical analysis of the colicin I receptor gene of Escherichia coli: Structural organization and transcriptional control mechanisms"]}]}],"canonical_facts":{"dc:contributor":["Konisky, Jordan"],"dc:creator":["Griggs, David William"],"dc:date":["2011-05-07T12:25:54Z","10000-01-01","1989"],"dc:description":["The cir gene, which encodes the colicin I receptor protein, is one of several outer membrane proteins synthesized by Escherichia coli in response to iron limitation. The location, organization, and regulation of cir and its neighboring genes were examined by a molecular genetic approach. Following cloning of the cir region, physical mapping and complementation analysis established the position of cir between mgl and nfo on the E. coli chromosome. A gene encoding a 32,000-dalton protein was located downstream of and adjacent to cir, was not part of the same transcriptional unit, and was not regulated by iron. The Cir protein was processed by removal of a signal peptide and the mature form had an amino terminal sequence which closely resembled that of other TonB-dependent proteins.","The molecular basis for iron-regulated expression of cir was investigated by genetic and biochemical means. Deletion analysis of the cloned promoter region allowed delineation of sequences necessary for control of transcription initiating at the two promoters P1 and P2. Gel retardation assays were used to demonstrate a highly specific interaction between purified Fur (ferric uptake regulation) protein and the iron control region. An operator sequence spanning 43-47 base pairs and completely encompassing the two promoters was identified by DNase I protection experiments, with binding occurring in a metal-dependent fashion. Thus, during iron replete growth, Fur appears to act as a repressor of transcription by blocking formation of a DNA-RNA polymerase complex. Expression of cir in an miaA mutant was comparable to that in a wild type strain, so no ancillary role in iron-regulation based on the modification of the affected tRNA species was detected. Characterized and putative Fur recognition sites from several genes were analyzed and classified by statistical methods.","In both high- and low-iron media, functional Crp protein and cyclic adenosine 3$\\sp\\prime$,5$\\sp\\prime$-monophosphate (cAMP) were required for maximal production of the receptor. A potential cAMP-CRP binding site located in the long leader region between the cir promoters and the start of the protein-coding region was suggested by sequence and mutational analysis.","Made available in DSpace on 2011-05-07T12:25:54Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 8916254.pdf: 4456928 bytes, checksum: b0883c8acab5481d85aab06001cae5f3 (MD5) Previous issue date: 1989","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T14:40:56Z Item is restricted indefinitely.","Restriction data tranferred 2014-07-01T11:17:38-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: ETDs are only available to UIUC Users without author permission","ETDs are only available to UIUC Users without author permission","U of I Only"],"dc:identifier":["AAI8916254","(UMI)AAI8916254","http://hdl.handle.net/2142/20009"],"dc:language":["eng"],"dc:rights":["Copyright 1989 Griggs, David William"],"dc:subject":["Biology, Molecular","Biology, Microbiology"],"dc:title":["Genetic and biochemical analysis of the colicin I receptor gene of Escherichia coli: Structural organization and transcriptional control mechanisms"],"dc:type":["text"],"thesis:degree_discipline":["Microbiology"],"thesis:degree_level":["Dissertation"],"thesis:degree_name":["Ph.D."],"thesis:institution_name":["University of Illinois at Urbana-Champaign"]},"updated_at":"2026-07-22T22:25:15Z"}