Evening star., 1939-04-09

- Sketch By Sudduth.
time-the way life is put together and
the weaknesses In the structure which
cause it to fall apart so easily.
Perhaps the outstanding accomplish
ments were those in the field of heavy
and radioactive isotopes which enable
chemists to look into the insides of iv-
ing cells and determine how living mat
ter is built up. The practical results
may not be apparent for years. but
neither were the practical results which
followed the analogous invention Of the
microscope which made it possible to see
the outsides of cells.
An extremely significant development
in this field was reported by Drs A.
Bramley and A. Keith Brewer of the
Bureau Of Chemistry and Soils It was
new method for separating isotopes of
gasses such as are used in inter-cellular
exploration. Actually the method was
first described by the German chemist,
Clusius. less than year ago and was
described by one chemist at the Balti-
more meeting who had not yet heard of
the improvements of Bramley and
Brewer as potentially the most impor-
tant discovery of our generation"
Weights Prove = Factor.
The atomic theory of matter, on which
is based the whole structure of modern
chemistry, supposes that the atoms of
the same elements are similar to one
another and equal In weight. At the
beginning of the present century scien-
lists began to suspect that many Of the
elements that make up the universe were
not simple substances. Now it is known
that most of the elements are made up
of two or more varieties of atoms with
almost identical chemical properties but
different weights. The different forms
of any element are called its 'isotopes."
1t was seemingly impossible task to
sort out these isotopes. The break came
about 10 years ago at the United States
Bureau of Standards with the produc-
ton of heavy water, containing double
weight hydrogen atoms. These could be
separated with comparative ease and
the discovery may be considered as one
of the turning points in the history of
science.
The method Of Clusius, as refined by
the Department of Agriculture chem
lists, makes it possible to produce the
heavier forms of almost any gas-or
anything that can be gotten into the
state of a gas-eventually in abundant
quantities.
How the method actually is being ap-
piled was described in a report by DR..
Vincent Du Vigneauld, last year pro-
fessor of biochemistry at George WASH
ington University, and now at Cornell.
DR.. Du Vigneauld is one of the worlds
foremost authorities on biological sui
phur compounds. Among them are two
Of the amino-acids, the substances into
which proteins in the food are broken
down by digestion. so that they can be
y methionine, present in milk, eggs, meat
and good many vegetables.
Essential to Life.
It is absolutely essential to life. With
out 1t all growth stops. This is just an
other way of saying, Dr. Du Vigneauld
otACooCo, CAAoo o44 AAAC oeOPo, oAAASC AAAS 40
growth
Still another. simpler in structure than
methionine but quite similar, is cystine.
It concentrates in the hair and nails,
but is probably essential for every organ
of the body. It enters into the makeup
of insulin, and also forms part of the
structure of pitressin and pitruitin, Sc
cretions OF the pituitary gland at the
base of the brain, which is considered the
governing organ of the subconscious life.
DR.. Du Vigneauld and his associates
sometime ago determined that rats could
live without cystine but not without
methionine, and there was evidence that
the latter was being changed into the
former by chemical reactions taking
place within the living cells.
DR.. Du Vigneauld had only to produce
synthetically not ordinary methionine
but deuterium methionine, in which the
atoms of heavy hydrogen, which perform
exactly alike chemically as the atoms of
light hydrogen, were used. He knew
where they were attached to the amino
acid molecule. Then he had only to
analyze the cystine of rats to which the
synthetic substance was fed and find
out what had become Of these heavy
hydrogen atoms.