{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,7]],"date-time":"2026-09-07T16:12:02Z","timestamp":1788797522912,"version":"build-2803163510"},"reference-count":28,"publisher":"Ovid Technologies (Wolters Kluwer Health)","issue":"2","license":[{"start":{"date-parts":[[2015,4,1]],"date-time":"2015-04-01T00:00:00Z","timestamp":1427846400000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/www.elsevier.com\/tdm\/userlicense\/1.0\/"},{"start":{"date-parts":[[2015,3,10]],"date-time":"2015-03-10T00:00:00Z","timestamp":1425945600000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001411","name":"Indian Council of Medical Research","doi-asserted-by":"publisher","award":["PHA-BMS-45\/94\/2012"],"award-info":[{"award-number":["PHA-BMS-45\/94\/2012"]}],"id":[{"id":"10.13039\/501100001411","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["lww.com","ovid.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2015,4]]},"abstract":"<jats:sec>\n                    <jats:title>Background:<\/jats:title>\n                    <jats:p>\n                      Dihydrofolate reductase (DHFR) (dfrA gene) is an essential enzyme for cell survival and an unexplored target in\n                      <jats:italic toggle=\"yes\">Mycobacterium tuberculosis<\/jats:italic>\n                      (Mtb). This study was carried out to analyze mutations in the dfrA gene amongst 20 clinical DNA samples from\n                      <jats:italic toggle=\"yes\">Mtb<\/jats:italic>\n                      isolates obtained from Mumbai, India.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods:<\/jats:title>\n                    <jats:p>\n                      Sequencing of the PCR amplified dfrA gene from these DNA isolates revealed a point mutation in one strain, leading to a glutamic acid to glycine change.\n                      <jats:italic toggle=\"yes\">in silico<\/jats:italic>\n                      simulation studies revealed a surface alteration in the enzyme due to this E84G mutation. The amplified mutant gene was cloned and expressed. The mutant protein was assessed against known DHFR inhibitors: Methotrexate and Trimethoprim.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results:<\/jats:title>\n                    <jats:p>An increased affinity for inhibitor Trimethoprim and native substrate dihydrofolate was observed with the mutant. Methotrexate did not vary in its activity with both the enzyme forms.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions:<\/jats:title>\n                    <jats:p>The Glu84Gly point mutation may lead to a variation in the strain which may cause resistance in the future.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1016\/j.ijmyco.2015.02.001","type":"journal-article","created":{"date-parts":[[2015,3,13]],"date-time":"2015-03-13T14:32:35Z","timestamp":1426257155000},"page":"97-103","update-policy":"https:\/\/doi.org\/10.1097\/lww.0000000000001000","source":"Crossref","is-referenced-by-count":13,"title":["E84G mutation in dihydrofolate reductase from drug resistant strains of Mycobacterium tuberculosis (Mumbai, India) leads to increased interaction with Trimethoprim"],"prefix":"10.4103","volume":"4","author":[{"given":"Archana","family":"Raju","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Savita","family":"Kulkarni","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"M.K.","family":"Ray","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"M.G.R.","family":"Rajan","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mariam S.","family":"Degani","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"276","reference":[{"key":"R1-3-20260907","doi-asserted-by":"crossref","first-page":"509","DOI":"10.1007\/BF01119794","article-title":"Nobel lecture, the purine path to chemotherapy","volume":"9","author":"Elion","year":"1989","journal-title":"Biosci. 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