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Published Papers
| Independent Functions of Viral Protein and Nucleic Acid in Growth of Bacteriophage. September 20, 1952. |
Page 04 [42]
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Authors: Martha Chase, Alfred Hershey
![Page 04 [42]](hersheychase-pg04-xl.jpg "Page 04 [42]")
Page 04 [42]
| Title: |
Independent Functions of Viral Protein and Nucleic Acid in Growth of Bacteriophage [4 of 18] |
| Creator: |
Chase, Martha |
| Contributor: |
Hershey, Alfred Day, 1908 |
| Publisher: |
Journal of General Physiology |
| Date: |
1952-09-20 |
| Subject: |
Molecular biology
Molecular genetics
|
| Description: |
From the Journal of General Physiology Vol. 36, No. 1. |
| Type: |
Text |
| Format: |
text/plain |
| Language: |
en |
| Identifier: |
hersheychase-pg04.jpg |
| Source: |
Master scanned with Epson GT-10000+ flatbed scanner at 600 dpi. |
| Rights: |
http://osulibrary.orst.edu/specialcollections/coll/pauling/dna/copyright.html |
| Full Text: |
42 VIRAL PROTEIN AND NUCLEIC ACID IN BACTERIOPIIAGE GROWTH
3. The ghosts are specifically adsorbed to phage-susceptible bacteria; the
DNA is not.
4. The ghosts represent protein coats that surround the DNA of the intact
particles, react with antiserum, protect the DNA from DNase (desoxyribo-
nuclease), and carry the organ of attachment to bacteria.
S. The effects noted are due to osmotic shock, because phage suspended in
salt and diluted slowly is not inactivated, and its DNA is not exposed to
DNase.
TABLE 11
Sensitization of Phage DNA to DNase by Adsorption to Bacteria
Non-seditnentable isotope,
Phage labeled per cent --
Phage adsorbed to with i ~ I
After DNase No DNase
Live bacteria................................ sib 2 1
it it P32 8 7
Bacteria heated before infection...... . ...... . . Sss 1S i 11
i
< << 11 P32 76 13
Bacteria heated after infection............ . . . . . su 12 14
t. tt << P" 66 23
70°....... P-
Heated unadsorbed phage: acid- 80°...... P" 13
soluble P32 90°...... P'z 81
100°....... Pn 88
Phage adsorbed to bacteria for 5 minutes at 37°C. in adsorption medium, followed by
washing.
Bacteria heated for 10 minutes at 80°C. in adsorption medium (before infection) or in
veronal buffer (after infection).
Unadsorbed phage heated in veronal buffer, treated with D- ase, and precipitated with
trichloroacetic acid.
All samples fractionated by centrifuging 10 minutes at 1300 G.
Sensitization of Phage DIVA to DNase by Adsorption to Bacteria. -The struc-
ture of the resting phage particle described above suggests at once the possibil-
ity that multiplication of virus is preceded by the alteration or removal of the
protective coats of the particles. This change might be expected to show itself
as a sensitization of the phage DNA to DNase. The experiments described
in Table 11 show that this happens. The results may be summarized as fol-
lows:-
1. Phage DNA becomes largely sensitive to DNase after adsorption to
heat-killed bacteria.
2. The same is true of the DNA of phage adsorbed to live bacteria, and then
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