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Rinehart, Kenneth L., Jr. Lau, Raymond Chung Man 2011-05-07T14:04:43Z 2011-05-07T14:04:43Z 10000-01-01 1990 ($\sp{13}$C$\sb6$) Glucose (3) was supplemented to seven-days old resting cells of neomycin B-proucing S.fradiae. The $\sp{13}$C NMR spectra of the enriched neomycin B (2) showed complex coupling patterns which suggested that 3 is not incorporated as an intact C$\sb6$ unit into the carbon skeleton of 2. These complex splitting patterns of 2 can be explained when 3 is first shunted through the pentose phosphate pathway to form primary metabolites of different carbon length. Some of these metabolites are then reconstituted back to six-carbon unit for the biosynthesis of 2. Two-dimensional NMR and FAB MS/MS studies have confirmed the structure of berninamycin A as proposed by Abe et al. Biosynthetic studies with $\sp{13}$C enriched amino acids showed that the dehydroalanines units were formed by dehydration of serine, the oxazoles were formed by condensing a threonine unit with a dehydrothreonine/dehydroalanine, the thiazole was formed by combining a cysteine with a dehydroalanine, and the biosynthesis of the pyridine ring was similar to the piperidine/hydroxypyridine ring formation in thiostrepton and nosiheptide. The biogensis of berninamycin A was discussed. Berninamycins B, C, and D were isolated by reverse-phased HPLC from S.bernensis. The structures of berninamycins B and D were studied with $\sp{13}$C NMR and FAB mass spectrometries. Berninamycin B was found to be deoxyberninamycin A with a valine unit instead of the $\beta$-hydroxyvaline unit of berninamycin A. Berninamycin D was found to have two less dehydroalanine units attached to the carboxyl carbon of the pyridine ring moiety. The structure of berninamycin C was postulated to have one less dehydroalanine unit attached to the carboxyl carbon of pyridine based on FABMS result. The biogeneses of these minor metabolites were discussed. Made available in DSpace on 2011-05-07T14:04:43Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9114306.pdf: 8660994 bytes, checksum: cef7b66e8b51067f2f611f9b64d7924b (MD5) Previous issue date: 1990 Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T15:02:40Z Item is restricted indefinitely. Restriction data tranferred 2014-07-01T11:29:49-05:00 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 AAI9114306 (UMI)AAI9114306 http://hdl.handle.net/2142/23172 eng Copyright 1990 Lau, Raymond Chung Man Chemistry, Organic Chemistry, Pharmaceutical Biosynthetic and structural studies of neomycin and berninamycin text Chemistry Chemistry University of Illinois at Urbana-Champaign Dissertation Ph.D.