Harley McAdams

Last updated
Harley McAdams
Born1938 (age 8485)
NationalityAmerican
Occupation(s)Professor of Developmental Biology
Microbial geneticist
Physicist
Spouse Lucy Shapiro

Harley H. McAdams (born 1938, Liberty, Texas) is an American physicist, microbial geneticist, and developmental biologist. McAdams and his collaborators have published foundational insights on the nature of genetic regulatory logic and cell biology, [1] [2] [3] the molecular basis for inevitable random variation levels of protein production between different cells, [4] [5] and genetic logic circuits that control the bacterial cell cycle. [6] [7] McAdams is married to Lucy Shapiro. They were jointly awarded the 2009 John Scott Medal for “bringing the methods of electrical circuit analysis to the description of genetic networks of the simple bacterium Caulobacter.” [8]

McAdams, a professor emeritus in the Department of Developmental Biology in the Stanford University School of Medicine, holds undergraduate and graduate degrees in physics from Texas A&M University (BS), the University of Illinois (Urbana) (MS), and Rice University (MA, PhD). He is a fellow of the American Society for Microbiology. [9]

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Xiaowei Zhuang is a Chinese-American biophysicist who is the David B. Arnold Jr. Professor of Science, Professor of Chemistry and Chemical Biology, and Professor of Physics at Harvard University, and an Investigator at the Howard Hughes Medical Institute. She is best known for her work in the development of Stochastic Optical Reconstruction Microscopy (STORM), a super-resolution fluorescence microscopy method, and the discoveries of novel cellular structures using STORM. She received a 2019 Breakthrough Prize in Life Sciences for developing super-resolution imaging techniques that get past the diffraction limits of traditional light microscopes, allowing scientists to visualize small structures within living cells. She was elected a Member of the American Philosophical Society in 2019 and was awarded a Vilcek Foundation Prize in Biomedical Science in 2020.

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CcrM is an orphan DNA methyltransferase, that is involved in controlling gene expression in most Alphaproteobacteria. This enzyme modifies DNA by catalyzing the transference of a methyl group from the S-adenosyl-L methionine substrate to the N6 position of an adenine base in the sequence 5'-GANTC-3' with high specificity. In some lineages such as SAR11, the homologous enzymes possess 5'-GAWTC-3' specificity. In Caulobacter crescentus Ccrm is produced at the end of the replication cycle when Ccrm recognition sites are hemimethylated, rapidly methylating the DNA. CcrM is essential in other Alphaproteobacteria but is role is not yet determined. CcrM is a highly specific methyltransferase with a novel DNA recognition mechanism.

References

  1. McAdams, H. H.; Shapiro, L. (1995). "Circuit simulation of genetic networks". Science . 269 (5224): 650–6. Bibcode:1995Sci...269..650M. doi:10.1126/science.7624793. PMID   7624793.
  2. Arkin, A.; Ross, J.; McAdams, H. H. (1998). "Stochastic kinetic analysis of developmental pathway bifurcation in phage lambda-infected Escherichia coli cells". Genetics . 149 (4): 1633–48. doi:10.1093/genetics/149.4.1633. PMC   1460268 . PMID   9691025.
  3. McAdams, H. H.; Arkin, A. (1998). "Simulation of prokaryotic genetic circuits". Annual Review of Biophysics and Biomolecular Structure. 27: 199–224. doi:10.1146/annurev.biophys.27.1.199. PMID   9646867.
  4. McAdams, H. H.; Arkin, A. (1999). "It's a noisy business! Genetic regulation at the nanomolar scale". Trends Genet. 15 (2): 65–69. doi:10.1016/S0168-9525(98)01659-X. PMID   10098409.
  5. McAdams, H. H.; Arkin, A. (1997). "Stochastic mechanisms in gene expression". Proc. Natl. Acad. Sci. U.S.A. 94 (3): 814–9. Bibcode:1997PNAS...94..814M. doi: 10.1073/pnas.94.3.814 . PMC   19596 . PMID   9023339.
  6. McAdams, H. H.; Shapiro, L. (2009). "System-level design of bacterial cell cycle control". FEBS Lett. 586 (2): 3984–3991. doi:10.1016/j.febslet.2009.09.030. PMC   2795017 . PMID   19766635.
  7. McAdams, H. H.; Shapiro, L. (2003). "A bacterial cell-cycle regulatory network operating in time and space". Science . 301 (5641): 3984–3991. Bibcode:2003Sci...301.1874M. doi:10.1126/science.1087694. PMID   14512618. S2CID   28742912.
  8. "The John Scott Award".
  9. "Stanford Profile, Harley H McAdams".