Stephen Kowalczykowski

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Stephen C. Kowalczykowski
Nationality American
Alma mater Rensselaer Polytechnic Institute, Georgetown University, University of Oregon
Known for DNA repair, homologous recombination, RecA, BRCA2, RecBCD, helicases, single-molecule biophysics
Awards Harvey Society Lecturer (2012)
American Academy of Arts and Sciences (2005)
National Academy of Sciences (2007)
Scientific career
Fields "Visual Biochemistry", Molecular Biology, Biophysics
Institutions University of California at Davis
Doctoral advisor Jacinto Steinhardt, Peter von Hippel

Stephen Charles Kowalczykowski ("Steve K") is a Distinguished Professor of Microbiology and Molecular Genetics at the University of California at Davis. His research focuses on the biochemistry and molecular biology of DNA repair and homologous recombination. His lab combines fluorescence microscopy, optical trapping and microfluidics to manipulate and visualize single molecules of DNA and the enzymes involved in processing and repairing DNA. He calls this scientific approach, "visual biochemistry".[1] Stephen Kowalczykowski was elected to the American Society for Arts and Science in 2005, the National Academy of Sciences in 2007 and was a Harvey Society Lecturer at Rockefeller University in 2012.[2][3]

Education and career[edit]

Stephen Kowalczykowski studied Chemistry (B.S.) at Rensselaer Polytechnic Institute in 1972 and earned his Ph.D. in Chemistry/Biochemistry at Georgetown University in 1976. His dissertation title was "Physical-Chemistry studies of Sickle Cell Hemoglobin." He then worked as a postdoctoral researcher with Dr. Peter von Hippel at the University of Oregon Health Sciences Institute, where he began studying the physical chemistry of protein-nucleic interactions. He began his academic research career at Northwestern University Medical School in 1981 and later moved to the University of California at Davis in 1991. He is one of the world's foremost experts on RecA, the defining member of a ubiquitous class of DNA strand-exchange proteins that are essential for homologous recombination, a pathway that maintains genomic integrity by repairing broken DNA. His lab has made significant contributions to the fields of DNA repair, homologous recombination and the biophysics of DNA helicases.

Scientific contributions[edit]

A few of his lab's notable scientific contributions include the structural and molecular mechanism of DNA end resection by RecBCD[4] (E. coli) and DNA2-Sgs1-RPA and regulatory stimulation by Top3-Rmi1 and Mre11-Rad50-Xrs2[5] (S. cerevisiae), the kinetics of RecA filament nucleation and growth[6] and regulation by RecFOR[7] (E. coli), the purification and molecular mechanism of the human breast cancer susceptibility gene BRCA2[8][9] (humans), the mechanism of the Holliday junction dissolution by the Bloom's Syndrome helicase (BLM) homologue, Sgs1[10][11] (S. cerevisiae), and the mechanism of the 3-dimensional homology search catalyzed by RecA[12] (E. coli).



  1. ^ "UC Davis College of Biological Sciences". Retrieved 22 February 2013. 
  2. ^ Retrieved 22 February 2013.  Missing or empty |title= (help)
  3. ^ Retrieved 22 February 2013.  Missing or empty |title= (help)
  4. ^ Singleton MR, Dillingham MS, Gaudier M, Kowalczykowski SC, Wigley DB (Nov 11, 2004). "Crystal structure of RecBCD enzyme reveals a machine for processing DNA breaks.". Nature. 432 (7014): 187–93. PMID 15538360. doi:10.1038/nature02988. 
  5. ^ Cejka P, Cannavo E, Polaczek P, Masuda-Sasa T, Pokharel S, Campbell JL, Kowalczykowski SC (Sep 2, 2010). "DNA end resection by Dna2-Sgs1-RPA and its stimulation by Top3-Rmi1 and Mre11-Rad50-Xrs2.". Nature. 467 (7311): 112–6. PMC 3089589Freely accessible. PMID 20811461. doi:10.1038/nature09355. 
  6. ^ Galletto R, Amitani I, Baskin RJ, Kowalczykowski SC (Oct 19). "Direct observation of individual RecA filaments assembling on single DNA molecules.". Nature. 443 (7113): 875–8. PMID 16988658. doi:10.1038/nature05197.  Check date values in: |date= (help)
  7. ^ Bell JC, Plank JL, Dombrowski CC, Kowalczykowski SC (Nov 8, 2012). "Direct imaging of RecA nucleation and growth on single molecules of SSB-coated ssDNA.". Nature. 491 (7423): 274–8. PMID 23103864. doi:10.1038/nature11598. 
  8. ^ Jensen RB, Carreira A, Kowalczykowski SC (Oct 7, 2010). "Purified human BRCA2 stimulates RAD51-mediated recombination.". Nature. 467 (7316): 678–83. PMC 2952063Freely accessible. PMID 20729832. doi:10.1038/nature09399. 
  9. ^ "Nature News". Retrieved 22 February 2013. 
  10. ^ Cejka P, Plank JL, Bachrati CZ, Hickson ID, Kowalczykowski SC (Nov 2010). "Rmi1 stimulates decatenation of double Holliday junctions during dissolution by Sgs1-Top3.". Nat Struct Mol Biol. 17 (11): 1377–82. PMC 2988882Freely accessible. PMID 20935631. doi:10.1038/nsmb.1919. 
  11. ^ Cejka P, Plank JL, Dombrowski CC, Kowalczykowski SC (Sep 28, 2012). "Decatenation of DNA by the S. cerevisiae Sgs1-Top3-Rmi1 and RPA complex: a mechanism for disentangling chromosomes.". Molecular Cell. 47 (6): 886–96. PMC 3462259Freely accessible. PMID 22885009. doi:10.1016/j.molcel.2012.06.032. 
  12. ^ Forget AL, Kowalczykowski SC (Feb 8, 2012). "Single-molecule imaging of DNA pairing by RecA reveals a three-dimensional homology search.". Nature. 482 (7385): 423–7. PMC 3288143Freely accessible. PMID 22318518. doi:10.1038/nature10782.