Myron L. Bender

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Myron Lee Bender
Born1924
St. Louis, Missouri
Died1988(1988-00-00) (aged 63–64)
Education Purdue University (B.S., Ph.D.)
Known for Hass–Bender oxidation
SpouseMuriel S. Bender
AwardsFellow of Merton College, Oxford University, National Academy of Sciences, 1968. Midwest Award of the American Chemical Society, 1972.
Scientific career
FieldsReaction mechanisms, biochemistry of enzyme action.
InstitutionsHarvard University, University of Chicago, Illinois Institute of Technology, Northwestern University
Doctoral advisor Henry B. Hass
Other academic advisors Paul D. Barlett, Frank H. Westheimer

Myron Lee Bender (1924–1988) was born in St. Louis, Missouri. He obtained his B.S. (1944) and his Ph.D. (1948) from Purdue University. The latter was under the direction of Henry B. Hass. After postdoctoral research under Paul D. Barlett (Harvard University), and Frank H. Westheimer (University of Chicago), he spent one year as a faculty member at the University of Connecticut. Thereafter, he was a professor of Chemistry at Illinois Institute of Technology in 1951, and then at Northwestern University in 1960. He worked primarily in the study of reaction mechanisms and the biochemistry of enzyme action. Myron L. Bender demonstrated the two-step mechanism of catalysis for serine proteases, nucleophilic catalysis in ester hydrolysis and intramolecular catalysis in water. He also showed that cyclodextrin can be used to investigate catalysis of organic reactions within the scope of host–guest chemistry. Finally, he and others reported on the synthesis of an organic compound as a model of an acylchymotrypsin intermediate.

Contents

During his career, Myron L. Bender was an active member of the Chicago Section of the American Chemical Society. He was elected a Fellow of Merton College, Oxford University, and to the National Academy of Sciences, the latter in 1968. He received an honorary degree from Purdue University in 1969. He was the recipient of the Midwest Award of the American Chemical Society in 1972.

Professor Bender retired from Northwestern in 1988. Both he and his wife, Muriel S. Bender, died that year.

Research

Research papers

Bender's initial work concerned mechanisms of chemical reactions, [1] and although this continued through his career he became increasingly interested in enzyme mechanisms, [2] especially that of α-chymotrypsin. [3] [4] [5] Later he broadened his interest to encompass other enzymes, such as acetylcholinesterase [6] and carboxypeptidase, [7] and others. [8]

Bender pioneered the use of p-nitrophenyl acetate as a model substrate for studying proteolysis, as it is particularly convenient in spectroscopic experiments. [9] [10] He likewise used imidazole as a model catalyst for shedding light on enzyme action. [11]

He also studied artificial enzymes, starting with modified subtilisin in which a serine residue was replaced by cysteine (replacing an ester group with a thiol). [12] Polgar and Bender laid stress on the fact that the modified enzyme was catalytically active, whereas Koshland and Neet, [13] who made essentially the same observation the same year, drew the opposite conclusion, that despite replacing group with one in principle more reactive, the modified enzyme was less effective as a catalyst than the unmodified enzyme. Philipp and Bender later did a detailed study of the catalytic differences between native subtilisin and thiolsubtilisin. [14] Bender also studied other artificial enzymes, [15] such as cycloamyloses, that were not simply modified natural enzymes.

Bender may have been the first to recognize that the specificity constant (, the ratio of catalytic constant to Michaelis constant) provides the best measure of enzyme specificity, [16] and to use the term specificity constant for it, as later recommended by the IUBMB. [17] Philipp and Bender proposed that this specificity constant is the same as the second-order rate constant for enzyme-substrate binding [18] for the most active substrates.

Reviews

Bender authored or co-authored several reviews, for example summarizing several years' work on α-chymotrypsin, [19] and proteolytic enzymes in general. [20]

Books

Bender's books primarily concerned catalysis, [21] especially catalysis by enzymes [22] and its underlying chemistry, [23] and also cyclodextrin chemistry; [24]

Bender Distinguished Summer Lecturers

The series of Myron L. Bender & Muriel S. Bender Distinguished Summer Lectures in Organic Chemistry was established in 1989 and hosted by the Department of Chemistry at Northwestern University. The scientists who have given these lectures include Julius Rebek (1990), JoAnne Stubbe (1992), Peter B. Dervan (1993), Marye Anne Fox (1994), Richard Lerner (1995), Eric Jacobsen (1997), Larry E. Overman (1998), Ronald Breslow (1999), Jean Fréchet (2000), Dale Boger (2001), |Barbara Imperiali (2003), François Diederich (2004), Christopher T. Walsh (2008), Stephen L. Buchwald (2009), Paul Wender (2010), and Kendall Houk (2011).

See also

Related Research Articles

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References

  1. ↑ Bender, Myron L. (1951). "Oxygen Exchange as Evidence for the Existence of an Intermediate in Ester Hydrolysis". Journal of the American Chemical Society. 73 (4): 1626–1629. doi:10.1021/ja01148a063.
  2. ↑ Bender, Myron L.; Turnquest, Byron W. (1957). "General Basic Catalysis of Ester Hydrolysis and Its Relationship to Enzymatic Hydrolysis1". Journal of the American Chemical Society. 79 (7): 1656–1662. doi:10.1021/ja01564a035.
  3. ↑ Bender, Myron L.; Kemp, Kenneth C. (1957). "The Kinetics of the α-Chymotrypsin-catalyzed Oxygen Exchange of Carboxylic Acids1". Journal of the American Chemical Society. 79: 116–120. doi:10.1021/ja01558a030.
  4. ↑ Bender, Myron L.; Glasson, William A. (1960). "The Kinetics of the α-Chymotrypsin-catalyzed Hydrolysis and Methanolysis of Acetyl-L-phenylalanine Methyl Ester. Evidence for the Specific Binding of Water on the Enzyme Surface1". Journal of the American Chemical Society. 82 (13): 3336–3342. doi:10.1021/ja01498a027.
  5. ↑ Bender, Myron L.; Zerner, Burt (1961). "The formation of the acyl-enzyme intermediate, trans-cinnamoyl-α-chymotrypsin, in the hydrolyses of non-labile trans-cinnamic acid esters1". Journal of the American Chemical Society. 83 (10): 2391–2392. doi:10.1021/ja01471a040.
  6. ↑ Bender, Myron L.; Stoops, James K. (1965). "Titration of the Active Sites of Acetylcholinesterase". Journal of the American Chemical Society. 87 (7): 1622–1623. doi:10.1021/ja01085a045. PMID   14302679.
  7. ↑ Bender, M. L.; Whitaker, J. R.; Menger, F. (1965). "The Effect of Enzyme Acetylation on the Kinetics of the Carboxypeptidase-A-Catalyzed Hydrolysis of Hippuryl-L-Phenyllactic Acid". Proceedings of the National Academy of Sciences. 53 (4): 711–716. doi: 10.1073/pnas.53.4.711 . PMC   221055 . PMID   14324526.
  8. ↑ Bender, Myron L.; Begué-Cantón, Maria Luisa Begué; Blakeley, Robert L.; Brubacher, Lewis J.; Feder, Joseph; Gunter, Claude R.; Kézdy, Ferenc J.; Killheffer, John V.; Marshall, Thomas H.; Miller, Charles G.; Roeske, Roger W.; Stoops, James K. (1966). "The Determination of the Concentration of Hydrolytic Enzyme Solutions: α-Chymotrypsin, Trypsin, Papain, Elastase, Subtilisin, and Acetylcholinesterase". Journal of the American Chemical Society. 88 (24): 5890–5913. doi:10.1021/ja00976a034. PMID   5980876.
  9. ↑ Bender, Myron L.; Turnquest, Byron W. (1957). "The Imidazole-catalyzed Hydrolysis of p-Nitrophenyl Acetate1". Journal of the American Chemical Society. 79 (7): 1652–1655. doi:10.1021/ja01564a034.
  10. ↑ Kezdy, Ferenc J.; Bender, Myron L. (1962). "The Kinetics of the α-Chymotrypsin-Catalyzed Hydrolysis of p-Nitrophenyl Acetate". Biochemistry. 1 (6): 1097–1106. doi:10.1021/bi00912a021. PMID   14032227.
  11. ↑ Westheimer, F. H.; Bender, Myron L. (1962). "Imidazole Catalysis of the Hydrolysis of δ-Thiovalerolactone". Journal of the American Chemical Society. 84 (24): 4908–4909. doi:10.1021/ja00883a055.
  12. ↑ Polgar, Laszlo; Bender, Myron L. (1966). "A New Enzyme Containing a Synthetically Formed Active Site. Thiol-Subtilisin1". Journal of the American Chemical Society. 88 (13): 3153–3154. doi:10.1021/ja00965a060.
  13. ↑ Neet, K. E.; Koshland, D. E. (1966). "The conversion of serine at the active site of subtilisin to cysteine: A "chemical mutation"". Proceedings of the National Academy of Sciences. 56 (5): 1606–1611. Bibcode:1966PNAS...56.1606N. doi: 10.1073/pnas.56.5.1606 . PMC   220044 . PMID   5230319.
  14. ↑ Philipp, Manfred; Bender, M. L. (1983). "Kinetics of subtilisin and thiolsubtilisin". Molecular and Cellular Biochemistry. 51 (1): 5–32. doi:10.1007/BF00215583. PMID   6343835. S2CID   24136200.
  15. ↑ Vander Jagt, David L.; Killian, Frederick L.; Bender, M. L. (1970). "Cycloamyloses as enzyme models. Effects of inclusion complex formation on intramolecular participation". Journal of the American Chemical Society. 92 (4): 1016–1022. doi:10.1021/ja00707a046. PMID   5451006.
  16. ↑ Brot, Frederick E.; Bender, Myron L. (1969). "Use of the specificity constant of α-chymotrypsin". Journal of the American Chemical Society. 91 (25): 7187–7191. doi:10.1021/ja01053a050.
  17. ↑ Cornish-Bowden, A. (2014). "Current IUBMB recommendations on enzyme nomenclature and kinetics". Perspectives in Science. 1 (1–6): 74–87. Bibcode:2014PerSc...1...74C. doi: 10.1016/j.pisc.2014.02.006 .
  18. ↑ Philipp, Manfred; Bender, Myron L. (1973). "Is binding the rate-limiting step in acylation of alpha-chymotrypsin by specific substrates?". Nature New Biology. 241 (106): 44. doi: 10.1038/newbio241044a0 . PMID   4512333.
  19. ↑ Bender, Myron L.; Kezdy, Ferenc J. (1964). "The Current Status of the α-Chymotrypsin Mechanism". Journal of the American Chemical Society. 86 (18): 3704–3714. doi:10.1021/ja01072a020.
  20. ↑ Bender, M. L.; Kezdy, F. J. (1965). "Mechanism of Action of Proteolytic Enzymes". Annual Review of Biochemistry. 34: 49–76. doi:10.1146/annurev.bi.34.070165.000405. PMID   14321178.
  21. ↑ Bender, Myron L. (1971). Mechanisms of Homogeneous Catalysis from Protons to Proteins. Wiley-Interscience. ISBN   978-0471065005.
  22. ↑ Bender, M. L.; Brubacher, Lewis J. (1973). Catalysis and Enzyme Action. McGraw-Hill. ISBN   978-0070044500.
  23. ↑ Bender, Myron L.; Bender, Mike; Bergeron, Raymond J.; Komiyama, Makoto (1984). The Bioorganic Chemistry of Enzymatic Catalysis. Wiley. ISBN   978-0471059912.
  24. ↑ Bender, Myron L; Kobiyama, M. (1978). Cyclodextrin Chemistry. Berlin: Springer-Verlag. ISBN   978-3540085775.
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