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Reflections on my career in analytical chemistry and biochemistry.

Sweeley CC - Proc. Jpn. Acad., Ser. B, Phys. Biol. Sci. (2010)

Bottom Line: Included here are the pioneering work on the gas chromatography of long-chain sphingolipid bases, carbohydrates, steroids and urinary organic acids.Mass spectrometry was utilized extensively in structural studies of sphingolipids, fatty acids, carbohydrates, steroids, urinary organic acids, polyisoprenoid alcohols, and juvenile hormone.The enzyme for hematoside synthesis was purified and characterized.

View Article: PubMed Central - PubMed

Affiliation: Department of Biochemistry, Michigan State University, East Lansing, Michigan 48823, USA. chucksweeley@comcast.net

ABSTRACT
My career has been focused in two major areas, analytical chemistry and biochemistry of complex lipids and glycoconjugates. Included here are the pioneering work on the gas chromatography of long-chain sphingolipid bases, carbohydrates, steroids and urinary organic acids. Mass spectrometry was utilized extensively in structural studies of sphingolipids, fatty acids, carbohydrates, steroids, urinary organic acids, polyisoprenoid alcohols, and juvenile hormone. Computer systems were developed for the acquisition and analysis of mass spectra, and were used for development of automated metabolic profiling of complex mixtures of metabolites. Fabry's disease was discovered to be a glycosphingolipidosis. Enzymes of lysosomal metabolism of glycosphingolipids were purified, characterized, and used in one of the first demonstrations of the feasibility of enzyme replacement therapy in a lysosomal storage disorder (Fabry's disease). Extracellular sialidases were studied to evaluate the hypothesis that they might be involved in the regulation of membrane growth factor receptors. The enzyme for hematoside synthesis was purified and characterized.

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Diastereoisomers of nicotine-1′-N-oxide.
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Related In: Results  -  Collection


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fig01: Diastereoisomers of nicotine-1′-N-oxide.

Mentions: The next project was to study the mechanism of a rearrangement reaction occurring when tertiary amine N-oxides were treated with a complex of ferric ion and tartaric acid.3) We found that N,N-dimethylglycine-N-oxide was effectively converted to sarcosine (N-methylglycine) and formaldehyde at room temperature by a transfer reaction of the oxygen atom to one of the methyl groups; transfer of the oxygen to the methylene atom of the glycine moiety gave dimethylamine and glyoxylic acid. A third, pH-dependent reaction yielded carbon dioxide, formaldehyde and dimethylamine.4) I wanted to see if the same rearrangement reactions would occur with nicotine-1′-N-oxide but discovered a complex of products which probably resulted from oxygen attack on the adjacent ring carbons as well as the N-methyl group. In preparing nicotine-1′-N-oxide, I was able to separate the two diastereoisomers resulting from the asymmetric quaternary pyrrolidine nitrogen atom (Fig. 1). Later studies by Phillipson and Handa5) provide an excellent overview of the chemistry and enzymology of the nicotine-N-oxides.


Reflections on my career in analytical chemistry and biochemistry.

Sweeley CC - Proc. Jpn. Acad., Ser. B, Phys. Biol. Sci. (2010)

Diastereoisomers of nicotine-1′-N-oxide.
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3037520&req=5

fig01: Diastereoisomers of nicotine-1′-N-oxide.
Mentions: The next project was to study the mechanism of a rearrangement reaction occurring when tertiary amine N-oxides were treated with a complex of ferric ion and tartaric acid.3) We found that N,N-dimethylglycine-N-oxide was effectively converted to sarcosine (N-methylglycine) and formaldehyde at room temperature by a transfer reaction of the oxygen atom to one of the methyl groups; transfer of the oxygen to the methylene atom of the glycine moiety gave dimethylamine and glyoxylic acid. A third, pH-dependent reaction yielded carbon dioxide, formaldehyde and dimethylamine.4) I wanted to see if the same rearrangement reactions would occur with nicotine-1′-N-oxide but discovered a complex of products which probably resulted from oxygen attack on the adjacent ring carbons as well as the N-methyl group. In preparing nicotine-1′-N-oxide, I was able to separate the two diastereoisomers resulting from the asymmetric quaternary pyrrolidine nitrogen atom (Fig. 1). Later studies by Phillipson and Handa5) provide an excellent overview of the chemistry and enzymology of the nicotine-N-oxides.

Bottom Line: Included here are the pioneering work on the gas chromatography of long-chain sphingolipid bases, carbohydrates, steroids and urinary organic acids.Mass spectrometry was utilized extensively in structural studies of sphingolipids, fatty acids, carbohydrates, steroids, urinary organic acids, polyisoprenoid alcohols, and juvenile hormone.The enzyme for hematoside synthesis was purified and characterized.

View Article: PubMed Central - PubMed

Affiliation: Department of Biochemistry, Michigan State University, East Lansing, Michigan 48823, USA. chucksweeley@comcast.net

ABSTRACT
My career has been focused in two major areas, analytical chemistry and biochemistry of complex lipids and glycoconjugates. Included here are the pioneering work on the gas chromatography of long-chain sphingolipid bases, carbohydrates, steroids and urinary organic acids. Mass spectrometry was utilized extensively in structural studies of sphingolipids, fatty acids, carbohydrates, steroids, urinary organic acids, polyisoprenoid alcohols, and juvenile hormone. Computer systems were developed for the acquisition and analysis of mass spectra, and were used for development of automated metabolic profiling of complex mixtures of metabolites. Fabry's disease was discovered to be a glycosphingolipidosis. Enzymes of lysosomal metabolism of glycosphingolipids were purified, characterized, and used in one of the first demonstrations of the feasibility of enzyme replacement therapy in a lysosomal storage disorder (Fabry's disease). Extracellular sialidases were studied to evaluate the hypothesis that they might be involved in the regulation of membrane growth factor receptors. The enzyme for hematoside synthesis was purified and characterized.

Show MeSH
Related in: MedlinePlus