Chapter 16: The Molecular Basis of Inheritance

xray 572.8092 FRA (Nichols) (VHS QH506 .S437 2003) Secret of Photo 51: 18:00 Wilkins uses condom 26:30 A and B forms 28:30 Watson/Crick initial model 37:00 Aaron Klug explains Photo 51
QH431 .D573 2002 Discovering DNA (IN LIBRARY USE)
 Watson/Crick: B form (wet), Franklin worked with Wilkins on A photo 51 ovarian 37; I94 2 mi S. of Gurnee Buckley Rd.
double_helix lab DNA MODEL
replication_fork Topoisomerase: break & rejoin backbone (PHONE CORD) Topoisomerase: the knotty problem of unwinding a double helix
replication_bubbles Double helix 2 nm wide.
elong Pol I fills gap & removes priner, II repair.
leading ZIPPER fannypack: leading strand
excision Nucleotide excision repair animation
telomere Telomerase is Reverse Transcriptase.
nucleosome A nucleosome has 8 histones w amino end (tail) out, separated by H1,.
===
OK        3=b  4=c  5=b 
6=d  7=a  8=c
  1. Rosalind Franklin King's College, work on X-ray diffraction DNA A (dry, denser) form, but photograph 51 was on B form (100 hours exposure), DNA was "face-centred monoclinic" space group shown by Wilkins to Watson & Crick, left King's in March 1953. Papers published in Nature April 1953 by Watson & Crick, another by Wilkins & Franklin. She had already prepared a draft paper describing the structure as a double helix when Crick and Watson produced theirs.
    Died in 1958 age 37 from ovarian cancer, only mentioned by Wilkins in lecture for 1962 Physiology or Medicine Prize. Only living persons can be nominated, Nobel archives closed 50 years. In 2008 whether Rosalind Franklin was ever a nominee.
  2. Maurice Wilkins was already carrying out X-ray diffraction analysis of DNA, B (wet) form. Francis Crick University of Cambridge.
  3. Linus Pauling 1953 triple helix theory. Chemistry Nobel 1954 chemical bonds & structure of molecules and crystals. 1962 Peace: 1958 petition protest nuclear testing, World Peace Research Organization in UN. Peter Pauling showed Watson & Crick preprint.
  4. Rosalind Franklin University, 3333 Green Bay Road, North Chicago, north of Evanston.
  5. DNA discovery.
  6. DNA repair: damage can be caused by base deamination or alkylation. Mismatched bases in E. coli not methylated yet after replication.
  7. Both leading-strand and lagging-strand telomeres replicate from a single parental telomere.
    FISH fluorescence in situ hybridization of telomeres.
  8. Polymerase: energy from deoxy-nucleotide-triphosphate.
  9. Fig 16.7 P.297: nucleotide .34 nanometers (nm) P. 301 6 billion base pairs = 2 meters DNA per cell. Ch 12 P. 220 200 trillion somatic cells.
  10. 100 repair enzymes in E. coli, 130 humans.