Vol. 13, No. 4, 1963
BIOCHEMICAL
AND BIOPHYSICAL RESEARCH COMMUNICATIONS
CBBOMATOGRAPBIC ANALYSIS OFpOLYPR'TlDESFROMPOLYRIBONUCLEOTIDE STIMUL4TEDENZYMATICSYNTBESIS
by Marvin A. Smith and Mark A. Stahmann
Department of Biochemistry,
University
of Wisconsin
Madison 6, Wisconsin
Received
August
29,
1963
In this communication we report the use of co-chromatography for fractionating
into polypeptides,
and the identity
peptiaes obtained from a partial Samples of the lysine-C laboratories
of lysine-C 14
products from the enzymatic incorporation
of these products with known poly-
hydrolyzate
14 polypeptides,
of synthetic
enzymatically
of Dr. S. Ochoa (Gardner gal.,
1962;
using a polyadenylic
acid (poly-A)
isolated
, were added to a partial
from E.
preparation
polylysine.
synthesized in the Kaziro et al.,
1963)
and an enzyme system acid hydrolyzate
of poly-
lysine and subjected to chrcmatography on carboxymethyl-cellulose All the radioactivity
in the enzymatically
recovered in the first
14 polylysine
recovered as dilysine,
but significant
polypeptides up to the tetradecamer. not significantly
greater
In such biosynthetic for the incorporation
columns.
synthesized products was
peaks.
The highest activity
was
was found in all
lysine
activity Activities
in larger peptiaes were
than background. systems, poly-A is considered to be the template
of lysine residues into polypeptldes.
Assuming that
the amino acid code requires a fixed nuniber of nucleotides for the incorporation
of each amino acid residue, one w0ula expect a correlation 251
Vol. 13, No. 4, 1963
BIOCHEMICAL
between the size of the po4-A
AND BIOPHYSICAL
and the size of the resulting
Consequently, a determination
of the size distribution
to stimulate the synthesis and of the po44sine the number of nucleotide residue.
Materials
These reaction inactivate
synthesized should reveal
and Methods.
of the polypeptides.
Aliquots
of the cell-free
provided by Drs. Y. Kaziro,
mixtures were boiled after
enzymes, and frozen until
described (Stewart,
J. W., et al.,
analyzed.
was prepared by partial
using techniques already
One ml of the reaction
columns. The carrier
acid hydrolysis
hydsolyzate
peptides from 4sine
220 mj.4was measured and
containing
passed through a flar
po44sine
acid for 80 minutes. of poly-
cell.
about 2O 4sine The absorbancy at
Aliquots were collected
recorded.
14 for determination of C activity.
Packard TM-Carb Scintlllatlon
Spectrometer.
was that described by Bray (1960).
was corrected for background, a quantitative
at s-minute
This was measured with a The scintillation
One nil. aliquots
were sdded to 10 ml of scintillation
added to the column was obtained.
mixture
po44sine
contained a continuous distribution
through polypeptides
The effluent
of the
of high molecular weight synthetic
hyarobromiae at 7O'C in 6 Ii hydrochloric
The resulting
residues.
Analysis was madeby
with 10 ml of water containing 10 mg of carrier
and added to carboxymethyl-cellulose
po44sine
A. Grossman and S. Ochoa.
1962) which allows resolution
2O homologous 4sine polypeptides.
was diluted
1. coli reaction
the incubation period to
co-chromatograplw on carboxymethyl-cellulose
fractions
of the poly-A used
residues required to code a single amino acid
of the size distribution
mixtures were kind4
intervals
poly-peptide.
In this communication we are concerned with the chromatographic
determination
first
RESEARCH COMMUNICATIONS
mixture
from each of the
mixture.
When the activity
recovery of the lysine-C
The operating efficiency
14
of the instrument
was about 47$. Results and Discussion. l(A)
The results are presented in Fig. 1.
shows that no incorporation
poly-A,
Figure
of lysine-C 14 occurred in the absence of
and that chromatography allowed separation of the first 252
2O 4sine
\‘ol. 13, No. 4, 1963
polypeptides
BIOCHEMICAL
in the carrier
AND BIOPHYSICAL
polylysine
from the incubation mixture.
hydrolyzate
RESEARCH COMMUNICATIONS
xith
Over 99$ of the radioactivity
lysine which did not interfere
no interference was eluted as
with separation of the higher peptides.
Less than l$ passed through with the frontal
peak as an acidic component.
!Chis may represent the maximumamount of lysine-C 14 that was linked to carrier
RNA. No incorporation
poly-A indicating initiation
into peptides occurred in the absence of
that peptide synthesis by routes other than poly-A
did not occur.
(A)
NO POLY
(B)
POLY
-A
-A
i ‘!l.,,j ,.,, ~~~~~,_..,,._.,...,_.,,, I’......:,% 50
100 FRACTION
150
NUMBER
Figure 1. Co-chromatography of lysine-C 14 incorporation products and known lysine polypeptides. (A) In the absence of poly-A stimulation. (B) With poly-A stimulation. (C) !Cungstate precipitate of poly-A stimulated system. The bars represent radioactivity in CPM, and the dots absorbancy at 220 q. Lysine polypeptides were eluted from carboxymethylcellulose columns with an exponential sodium chloride gradient (Stewart et al., 1962). Peaks following the large frontal peals are lysine and consecutive oligomers, except the small peak following dimer in (A) and (B) which originates from the incubation mixture. The last large broad peak represents high molecular weight material eluted by increasing the gradient rate. 253
Vol. 13, No. 4, 1963
BIOCHEMICAL
The results in Fig. l(B).
AND BIOPHYSICAL
obtained when poly-A was added to this system are shown
Radioactivity
was recovered with lysine and all
containing from 2-14 lysine residues. dilysine.
peptides
Almost half was recovered as
This may arise from the cleavage of poly-A by ribonucleases
to fragments that code for dilysine, try-ptic-like
(Stewart,
or the cleavage of polylysine
enzymes. However, the distribution
was different
exactly
RESEARCH COMMUNICATIONS
from that obtained on tryptic
N. IL, 1962).
The position
with the position
significant
radioactivity
of the radioactivity
hydrolysis
of polylysine
of the radioactivity
of peptides in the partial
coincided No
acid hydrolyzate.
was detected in peptides containing more than 14
The increase in activity
lysine residues.
by
octa-lysine
polypeptides,
significant
and may be a reflection
as
recovered in the hepta- and
compared with neighboring polypeptiaes, of the size distribution
is
of the p&y-A
used to stimulate the biosynthesis. The products from a similar trichloroacetic precipitate
acid-sodium tungstate
was extracted
products analyzed after in Fig. l(C) indicate
1962).
This
with j$ ammonium hydroxide and the soluble
that the tungstate does not precipitate of the lower lysine polypeptiaes
dilysine
enzymatic
co-chromatographed with known lysine polypeptides,
conclude that poly-A
stimulation
results
shown
in incomplete.
Since products from goly-A stimulated
Conclusions.
lysine.
(Gardner et al.,
with
removing the excess ammonia. The results
and that precipitation
biosynthesis
experiment were precipitated
in the biosynthesis
we
of poly-
!Pryptic degradation of these products have been shownto form
the samepeptides as those from polylysine Chromatography on carbovthyl-cellulose the species formed in the biosynthetic Polynucleic
was adequate to separate all reactions.
(Khorana et al.,
between the size of the initiating
of the resulting
1963).
acids have been separated by chromatography on
diethylaminoethyl-cellulose correlation
(Kaziro et al.,
polypeptide
1961).
If there is a
nucleic acid and the size
it would follow that chromatographic analysis 254
Vol. 13, No. 4, 1963
BIOCHEMICAL
AND BIOPHYSICAL RESEARCH COMMUNICATIONS
of the nucleic acid and the resulting relationship.
polypeptide
should reveal this
However, such experiments are complicated by the cleavage
of nucleic acids or the peptides during the experiment. results
indicate
as dilysine,
that more than half of the radioactive
and as the distribution
this is not entirely dilysine active
due to tryptic
hydrolysis,
we suggest that the
stimulated by the most abundant
poly-A species in the reaction mixture.
important to determine the size distribution
produced.
lysine was found
of the poly-peptides suggests that
may arise from a biosynthesis
and to correlate
Inasmuch as our
It would therefore of the poly-A after
this with the size distribution
of the polylysine
seem incubation peptides
This may reveal the number of nucleotide residues required to
code single amino acid residues.
Acknowledmnts. The authors wish to express their gratitude to Drs. S. Ochoa. Y. Kaziro and A. Grossmanfor the E. coli incubation mixtures used'in this work. The investigation was supported by grants E 101 and GPM-14, 6724~~ from the National Institutes of Health, U. S. Public Health Service.
References Bray, G. A., Anal. Biochem., ?., 279 (1960). Gardner, R. S., Wahba, A. J., Basilio, C., Miller, R. S., Lengyel, P., and Speyer, J. F., Proc. Nat. Acad. Sci., 48, 2087 (1962). Grossman, A., and Ochoa, S., Proc. Nat. Acad. Sci., so, 54 K-iry&. Worana, H. G., cznd Vizsolyi, J. P., J. Am. Chem. sot., 83, 675 (1961). Stewart, J. W., and Stahmann, M. A., J. Chromatography, 2, 233 (1962); Polysmino Acids, Polypeptides and Proteins, Stahmann, M. A., ea., p. 95, University of Wisconsin Press, Madison, Wis., 1962. Stewart, N. K., M.S. Thesis, University of Wisconsin, Madison, Wis., 1962.