Arye Tishbee - Academia.edu (original) (raw)

Papers by Arye Tishbee

Journal of the American Chemical Society, 1980

Journal of the American Chemical Society, 1980

Journal of Chromatography A, 1981

Silica gel which is physically coated with a solid substance is still a useful stationary phase i... more Silica gel which is physically coated with a solid substance is still a useful stationary phase in liquid chromatography (LC), in spite of the high performance of other LC systems. Such coated systems have been shown to be advantageous for the separation of geometric* and optical isomers *s3-transition-metal complexesJ*5 and , charge-transfer acceptors for complexation with polyaromatic hydrocarbons (PAHs)'" are typical examples. In sit&' coating is a generally accepted method, but this technique possesses intrinsic problems, such as inhomogeneity of the coating and uncertainty of the amount of the coating material_ In the course of high-performance liquid chromatography studies on charge-transfer complexation between biological compounds with PAHs we observed that the amount of coatin g on silica gel seriously affects the column performance_ We report here the influence of the amount of riboflavin (vitamin B,). the coating material, on silica gel for PAH separation.

Analytical Chemistry, 1973

Profiles of volatile metabolites of 150 urine samples from normal individuals and 40 samples from... more Profiles of volatile metabolites of 150 urine samples from normal individuals and 40 samples from subjects with diabetes mellitus have been studied by gas chromatography and mass spectrometry. The technique involves adsorption of the urinary headspace volatiles on Tenax GC, heat desorption with helium, trapping on a cooled precolumn, and chromatography on 100-m X 0.50-mm i.d. nickel columns. Individual profiles were observed over a period of 2 months. Characteristic constituents in normal urines are 2-butanone, 2-pentanone, 4-heptanone, dimethyl disulfide, several alkyl furans, pyrrole, and carvone. In subjects with diabetes mellitus under insulin treatment, high concentrations of pyrazines, cyclohexanone, lower aliphatic alcohols, and octanols were found.

Biochemistry, 2006

There is evidence that some products of the reaction of ozone with cholesterol contribute to athe... more There is evidence that some products of the reaction of ozone with cholesterol contribute to atherosclerosis. One of these compounds is 3beta-hydroxy-5-oxo-5,6-secocholestan-6-al. We have synthesized this compound and have demonstrated that it reacts with phosphatidylethanolamine to form a Schiff base. The 3beta-hydroxy-5-oxo-5,6-secocholestan-6-al also affects the physical properties of phosphatidylethanolamines. We show by both DSC and X-ray diffraction that it increases the negative curvature of the membrane. In addition, 3beta-hydroxy-5-oxo-5,6-secocholestan-6-al causes the lamellar phase to become disorganized, resulting in the loss of lamellar periodicity. The chemical and physical interactions of 3beta-hydroxy-5-oxo-5,6-secocholestan-6-al with phosphatidylethanolamines may contribute to damaging effects of this lipid on cell membranes, resulting in pathology.

Journal of the Chemical Society, Chemical Communications, 1981

* Chromatographic conditions: column dimensions = 15 x 0-46 cm; flow rate = 0.7 ml/min; ambient t... more * Chromatographic conditions: column dimensions = 15 x 0-46 cm; flow rate = 0.7 ml/min; ambient temperature. b For numberd a = resolution ing, see the general formulae (A) and (B). factor = ki/ki = ratio of capacity factors of the two enantiomers. C Both the racemic and (-)-enantiomeric compounds were available.

Chemischer Informationsdienst, 1980

Journal of Liquid Chromatography, 1983

Origin of Life, 1981

The investigation of a number of important problems in research on the origins of life hinges on ... more The investigation of a number of important problems in research on the origins of life hinges on the determination of the configuration or enantiomeric composition of optically active substances of biological significance. There are many biological molecules which, in principle, could serve as the asymmetric probes in relevant experiments. However, for a variety of reasons, protein amino acids are, at least thus far, the most suitable class of compounds for such studies.

Origin of Life, 1981

In a preceding communication from this laboratory (1) we have discussed the importance of chromat... more In a preceding communication from this laboratory (1) we have discussed the importance of chromatographic methods for the resolution of optical isomers as tools in research on problems related to the origins of life. Besides its analytical significance, the study of chromatographic separation based on stereo-selective interactions between chiral molecules acting, respectively, as selectors and selectands (2), has also considerable interest for the development of concepts on chiral recognition and its mechanism (3,4). The ideas evolved could be relevant to the problem of amplification of optical activity discussed in this section. This is particularly true for systems involving biological molecules.

J. Chem. Soc., Chem. Commun., 1982

ABSTRACT Derivatives of α- amino-acid esters containing a strong electron acceptor group, were re... more ABSTRACT Derivatives of α- amino-acid esters containing a strong electron acceptor group, were resolved on silica gel coated with a chiral electron donor substance.

Rapid Communications in Mass Spectrometry, 2013

RATIONALE: We describe a novel negative chemically activated fragmentation/positive chemically ac... more RATIONALE: We describe a novel negative chemically activated fragmentation/positive chemically activated fragmentation (CAFÀ/CAF+) technique for protein identification. The technique was used to investigate Lactobacillus brevis adaptation to nutrient deprivation. METHODS: The CAFÀ/CAF+ method enables de novo sequencing of derivate peptides with negative and positive ion mode matrix-assisted laser desorption/ionization (MALDI) tandem mass spectrometry (MS/MS). Peptide sequences obtained from MS/MS spectra were matched against the National Center for Biotechnology Information (NCBI) nonredundant (nr) database and confirmed by the mass spectrometry data of elucidated peptide mass sequences derived from the annotated genome. This improved protein identification method highlighted 36 differentially expressed proteins in the proteome of L. brevis after 75 days of starvation. RESULTS: The results revealed the key differences in the metabolic pathways that are responsible for the survival of L. brevis in a hostile environment. Proteomics analysis demonstrated that numerous proteins engaged in glucose and amino-acid catabolizing pathways, glycerolipid metabolizing pathways, and stress-response mechanisms are differentially expressed after long-term starvation. Amino acid and proteomics analysis indicated that starved L. brevis metabolized arginine, glycine, and histidine from dead cells as alternative nutrient sources. The production of lactic acid also varied between the parent cells and the starved cells. CONCLUSIONS: Differentially expressed proteins identified exclusively by peptide sequence reading provided promising results for CAFÀ/CAF+ implementation in a standard proteomics workflow (e.g., biomarker and mutation discovery and biotyping). The practical performance of a reliable de novo sequencing technique in routine proteomics analysis is emphasized in this article.

Journal of the American Chemical Society, 1982

Journal of Chromatography A, 1981

Journal of Chromatography A, 1975

An electron capture detector has been constructed which uses photoionization to produce the elect... more An electron capture detector has been constructed which uses photoionization to produce the electrons, thus eliminating the conventional use of a radioactive source for this purpose. A photo-electron capture detector was investigated using the Lyman-a resonance line of hydrogen with triethylamine. The detector was operated in the d.c. mode and attained a limit of sensitivity for carbon tetrachloride of 50 pg.

Journal of Chromatographic Science, 1973

Chromatographia, 1973

A new procedure for sampling, transfer, and analysis of volatile organic compounds by gas chromat... more A new procedure for sampling, transfer, and analysis of volatile organic compounds by gas chromatography has been developed. An adsorbent trap ultimately becomes an insert for a modified injector port, and a valve system allows the sample to be transferred to a cooled precolumn and finally to the separating column. Several traps may be used for sampling (for multiple injections), and it has been established that such traps maF be stored without loss of sample. The ease and reproducibilit/ of this procedure is amenable for the investigation of volatile organic compounds involving air and water pollution, flavor, and aroma analFses, and body fluid metabolites. Of the three chromatographic packing materials studied in this investigation, Tenax GC proved to be superior as a general adsorbent, even though insufficient chromatographic separation data has been established for certain organic compounds. This only implies that more studies are needed if Tenax GC is to be used as a partial trapping system. a) Porapak P Porapak P, (Waters Associates, Framingham, Massachusetts), a porous polymer of styrene and divinylbenzene, was first employed as an adsorbent, and appeared to suffice as a sampling system, but certain limitations became apparent. The temperature limit of 230 o C was a critical factor, since desorption by heat was limited to 200 ~ and the ensuing bleeding produced artifacts upon analysis.

Journal of the American Chemical Society, 1980

Journal of the American Chemical Society, 1980

Journal of Chromatography A, 1981

Silica gel which is physically coated with a solid substance is still a useful stationary phase i... more Silica gel which is physically coated with a solid substance is still a useful stationary phase in liquid chromatography (LC), in spite of the high performance of other LC systems. Such coated systems have been shown to be advantageous for the separation of geometric* and optical isomers *s3-transition-metal complexesJ*5 and , charge-transfer acceptors for complexation with polyaromatic hydrocarbons (PAHs)'" are typical examples. In sit&' coating is a generally accepted method, but this technique possesses intrinsic problems, such as inhomogeneity of the coating and uncertainty of the amount of the coating material_ In the course of high-performance liquid chromatography studies on charge-transfer complexation between biological compounds with PAHs we observed that the amount of coatin g on silica gel seriously affects the column performance_ We report here the influence of the amount of riboflavin (vitamin B,). the coating material, on silica gel for PAH separation.

Analytical Chemistry, 1973

Profiles of volatile metabolites of 150 urine samples from normal individuals and 40 samples from... more Profiles of volatile metabolites of 150 urine samples from normal individuals and 40 samples from subjects with diabetes mellitus have been studied by gas chromatography and mass spectrometry. The technique involves adsorption of the urinary headspace volatiles on Tenax GC, heat desorption with helium, trapping on a cooled precolumn, and chromatography on 100-m X 0.50-mm i.d. nickel columns. Individual profiles were observed over a period of 2 months. Characteristic constituents in normal urines are 2-butanone, 2-pentanone, 4-heptanone, dimethyl disulfide, several alkyl furans, pyrrole, and carvone. In subjects with diabetes mellitus under insulin treatment, high concentrations of pyrazines, cyclohexanone, lower aliphatic alcohols, and octanols were found.

Biochemistry, 2006

There is evidence that some products of the reaction of ozone with cholesterol contribute to athe... more There is evidence that some products of the reaction of ozone with cholesterol contribute to atherosclerosis. One of these compounds is 3beta-hydroxy-5-oxo-5,6-secocholestan-6-al. We have synthesized this compound and have demonstrated that it reacts with phosphatidylethanolamine to form a Schiff base. The 3beta-hydroxy-5-oxo-5,6-secocholestan-6-al also affects the physical properties of phosphatidylethanolamines. We show by both DSC and X-ray diffraction that it increases the negative curvature of the membrane. In addition, 3beta-hydroxy-5-oxo-5,6-secocholestan-6-al causes the lamellar phase to become disorganized, resulting in the loss of lamellar periodicity. The chemical and physical interactions of 3beta-hydroxy-5-oxo-5,6-secocholestan-6-al with phosphatidylethanolamines may contribute to damaging effects of this lipid on cell membranes, resulting in pathology.

Journal of the Chemical Society, Chemical Communications, 1981

* Chromatographic conditions: column dimensions = 15 x 0-46 cm; flow rate = 0.7 ml/min; ambient t... more * Chromatographic conditions: column dimensions = 15 x 0-46 cm; flow rate = 0.7 ml/min; ambient temperature. b For numberd a = resolution ing, see the general formulae (A) and (B). factor = ki/ki = ratio of capacity factors of the two enantiomers. C Both the racemic and (-)-enantiomeric compounds were available.

Chemischer Informationsdienst, 1980

Journal of Liquid Chromatography, 1983

Origin of Life, 1981

The investigation of a number of important problems in research on the origins of life hinges on ... more The investigation of a number of important problems in research on the origins of life hinges on the determination of the configuration or enantiomeric composition of optically active substances of biological significance. There are many biological molecules which, in principle, could serve as the asymmetric probes in relevant experiments. However, for a variety of reasons, protein amino acids are, at least thus far, the most suitable class of compounds for such studies.

Origin of Life, 1981

In a preceding communication from this laboratory (1) we have discussed the importance of chromat... more In a preceding communication from this laboratory (1) we have discussed the importance of chromatographic methods for the resolution of optical isomers as tools in research on problems related to the origins of life. Besides its analytical significance, the study of chromatographic separation based on stereo-selective interactions between chiral molecules acting, respectively, as selectors and selectands (2), has also considerable interest for the development of concepts on chiral recognition and its mechanism (3,4). The ideas evolved could be relevant to the problem of amplification of optical activity discussed in this section. This is particularly true for systems involving biological molecules.

J. Chem. Soc., Chem. Commun., 1982

ABSTRACT Derivatives of α- amino-acid esters containing a strong electron acceptor group, were re... more ABSTRACT Derivatives of α- amino-acid esters containing a strong electron acceptor group, were resolved on silica gel coated with a chiral electron donor substance.

Rapid Communications in Mass Spectrometry, 2013

RATIONALE: We describe a novel negative chemically activated fragmentation/positive chemically ac... more RATIONALE: We describe a novel negative chemically activated fragmentation/positive chemically activated fragmentation (CAFÀ/CAF+) technique for protein identification. The technique was used to investigate Lactobacillus brevis adaptation to nutrient deprivation. METHODS: The CAFÀ/CAF+ method enables de novo sequencing of derivate peptides with negative and positive ion mode matrix-assisted laser desorption/ionization (MALDI) tandem mass spectrometry (MS/MS). Peptide sequences obtained from MS/MS spectra were matched against the National Center for Biotechnology Information (NCBI) nonredundant (nr) database and confirmed by the mass spectrometry data of elucidated peptide mass sequences derived from the annotated genome. This improved protein identification method highlighted 36 differentially expressed proteins in the proteome of L. brevis after 75 days of starvation. RESULTS: The results revealed the key differences in the metabolic pathways that are responsible for the survival of L. brevis in a hostile environment. Proteomics analysis demonstrated that numerous proteins engaged in glucose and amino-acid catabolizing pathways, glycerolipid metabolizing pathways, and stress-response mechanisms are differentially expressed after long-term starvation. Amino acid and proteomics analysis indicated that starved L. brevis metabolized arginine, glycine, and histidine from dead cells as alternative nutrient sources. The production of lactic acid also varied between the parent cells and the starved cells. CONCLUSIONS: Differentially expressed proteins identified exclusively by peptide sequence reading provided promising results for CAFÀ/CAF+ implementation in a standard proteomics workflow (e.g., biomarker and mutation discovery and biotyping). The practical performance of a reliable de novo sequencing technique in routine proteomics analysis is emphasized in this article.

Journal of the American Chemical Society, 1982

Journal of Chromatography A, 1981

Journal of Chromatography A, 1975

An electron capture detector has been constructed which uses photoionization to produce the elect... more An electron capture detector has been constructed which uses photoionization to produce the electrons, thus eliminating the conventional use of a radioactive source for this purpose. A photo-electron capture detector was investigated using the Lyman-a resonance line of hydrogen with triethylamine. The detector was operated in the d.c. mode and attained a limit of sensitivity for carbon tetrachloride of 50 pg.

Journal of Chromatographic Science, 1973

Chromatographia, 1973

A new procedure for sampling, transfer, and analysis of volatile organic compounds by gas chromat... more A new procedure for sampling, transfer, and analysis of volatile organic compounds by gas chromatography has been developed. An adsorbent trap ultimately becomes an insert for a modified injector port, and a valve system allows the sample to be transferred to a cooled precolumn and finally to the separating column. Several traps may be used for sampling (for multiple injections), and it has been established that such traps maF be stored without loss of sample. The ease and reproducibilit/ of this procedure is amenable for the investigation of volatile organic compounds involving air and water pollution, flavor, and aroma analFses, and body fluid metabolites. Of the three chromatographic packing materials studied in this investigation, Tenax GC proved to be superior as a general adsorbent, even though insufficient chromatographic separation data has been established for certain organic compounds. This only implies that more studies are needed if Tenax GC is to be used as a partial trapping system. a) Porapak P Porapak P, (Waters Associates, Framingham, Massachusetts), a porous polymer of styrene and divinylbenzene, was first employed as an adsorbent, and appeared to suffice as a sampling system, but certain limitations became apparent. The temperature limit of 230 o C was a critical factor, since desorption by heat was limited to 200 ~ and the ensuing bleeding produced artifacts upon analysis.