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Proline betaine is a highly effective osmoprotectant for Staphylococcus aureus
13C NMR studies revealed that proline betaine accumulated to high levels in osmotically stressed S. aureus, but was also detected in organisms grown in its presence in the absence of osmotic stress. Expand
The enigma of coproporphyrinogen oxidase: how does this unusual enzyme carry out oxidative decarboxylations to afford vinyl groups?
  • T. D. Lash
  • Chemistry, Medicine
  • Bioorganic & medicinal chemistry letters
  • 15 October 2005
A new mechanism is proposed to explain how coproporphyrinogen oxidase performs two oxidative decarboxylations on a porphyrinogen substrate without the aid of cofactors or metal ions in the presenceExpand
Neo-confused porphyrins, a new class of porphyrin isomers.
Unusual Peroxide-Dependent, Heme-Transforming Reaction Catalyzed by HemQ.
The ability of peracetic acid to substitute for H2O2 suggests that, despite the lack of catalytic residues conventionally present in heme peroxidase active sites, reaction pathways involving high-valent iron intermediates cannot be ruled out. Expand
Porphyrins with exocyclic rings. Part 9 [1] Synthesis of porphyrins by the ‘3 + 1’ approach
Tripyrrane dibenzyl esters are readily available from the reaction of two equivalents of 5-acetoxymethylpyrrole-2-carboxylates with 2,5-diunsubstituted pyrroles in refluxing acetic acid-ethanol.Expand
Normal and Abnormal Heme Biosynthesis. 1. Synthesis and Metabolism of Di- and Monocarboxylic Porphyrinogens Related to Coproporphyrinogen-III and Harderoporphyrinogen: A Model for the Active Site of
Coproporphyrinogen oxidase (copro'gen oxidase), which catalyses the conversion of coproporphyrinogen-III via a monovinylic intermediate to protoporphyrinogen-IX, is one of the least well understoodExpand
Synthesis, structural characterization, aromatic characteristics, and metalation of neo-confused porphyrins, a newly discovered class of porphyrin isomers.
Proton NMR spectroscopy demonstrates that the diatropic character of this system is diminished compared to regular porphyrins, although neo-confused porph Pyrrole-3-carbaldehydes and 5-acetoxymethylpyrrole-2-carbaldehyde intermediates retain porphyrsin-like UV-vis spectra. Expand
Transport of thiamine and 4-methyl-5-hydroxyethylthiazole by Salmonella typhimurium.
Results were obtained with attempts to replace MAHMP as a growth requirement for a purD mutant of Salmonella typhimurium, and 2-Methyl-4-amino-5-methoxymethylpyrimidine were unable to replaceMAHMPAs stimulators of MHET uptake, but 2-methyl-4/5-aminomethylpyridine was marginally effective in this regard. Expand
Aromatic character and relative stability of neo-confused porphyrin tautomers and related compounds.
Nucleus independent chemical shifts (NICS) demonstrated that the fully conjugated neo-CP and B-neo-CP tautomers exhibit a significant amount of diatropic character, but these values are somewhat lower than the results obtained for porphyrins, BPs or BCPs. Expand
Transport of 2-methyl-4-amino-5-hydroxymethylpyrimidine by Salmonella typhimurium.
The transport of 2-methyl-4-amino-5-hydroxymethylpyrimidine (MAHMP) by Salmonella typhimurium was studied using synthetic [methyl-3H3]MAHMP. It was found that an active transport system existed forExpand