LIFE IS THE BEGINNING

Evening Star, Issue 22688, 30 June 1937, Page 18

LIFE IS THE BEGINNING

THE INVISIBLE PARASITES DOCTOR'S DARING THEORY [By E. S. Grew in the ‘ Observer.’] At a meeting of the British Association, when its president, Sir E. Sharpoy Schaefer, had renewed the perennial question of the ‘ Origin of Life,’ ono of the zoologists, Professor Aiinchin, said there could never bs an answer. A living thing could never be shown to be a mere arrangement of atoms and electric forces. We might believe it was or was not, but our belief or disbelief merely served to show the kind of mind we had. It could never be proved either way. A r et, belief of either kind dies hard. There are always many scientists unalterably expectant of finding something to show that a rearrangement, by chance or intent, of the atoms of a substance that is certainly not alive may make it live. Or, conversely, a thing having the characters of life may be shown to be reducible to a lifeless assemblage of atoms without losing its individuality. The latest search for this proof is among the bits of life which have thrust themselves on our attention as the viruses, and which were declared by some to be far too small to be organised living things at all. They are, in fact, of a number of different sizes, but nearly all are so small as to be invisible. Influenza virus is the one most spoken of, though the virus of the common cold runs it close. But it is a far less inconvenient virus than those of the virus producing the mosaic disease of tobacco plants that has started the old argument anew. ALIVE OR DEAD? It has now leapt into the limelight because of the assertion that it is not a veritable living organism, though it has the attributes of one, in producing, almost as if it were a germ, a disease in the tobacco leaf ns it spreads among the plant cells, or when it is transplanted from one leaf to another. If it is not alive, then what is it? Is it a poison that can multiply itself, and, if so, what sort of a poison can this he? An answer offered by Dr W. AL Stanley and received with acclamation in America and less enthusiasm in England, is that, first of all, it is a crystal. Dr Stanley crystallised out tho tobacco masaie virus, and showed that the crystals would produce tho disease again. He went further'on this path of inquiry. He sent some of the crystals for examination to Professor Svedberg, whose ultra centrifuges for measuring the size of invisible things were described in the ‘ Observer ’ last November, and the size of the molecule of these crystals was determined. It proved to bo a molecule only one-four-teenth the size of Iho smallest bacteria. Dr Stanley concluded that it was a molecule of protein, the stuff we generally associate with our daily food, but which, in this example of it, was a poison, and bad besides the strange property of spreading poisononsness wherever it might be. But it was not alive. Tho inference drawn by the more daring followers of this discovery is that some chance rearrangement of the atoms in such a protein molecule may make it come alive. THE VITAL LINK. In other words, here is a beginning of life. The viruses may be the link between the quick and the dead. The idea has the fascination of all such speculations. It is natural to seek the origin of life in some of the most primitive examples of it, and the viruses because of their smallness invito such examination, whale at the same time offering by their invisibility as individuals powerful obstacles to it. They are a mixed bag in size as well as character, but, though some must be assigned measurements of no more than a few hundred-thousandths of an inch, the suggestion that they are too small to bo living organisms may be dismissed. The parcels into which life can be packed are almost incredibly small. Half an aspirin tablet would be large enough to contain 2,000 million germ cells of a human being. Yet all the intricate characteristics of a future generation are contained in one of them. In the cell is its nucleus, its indispensable promoter of life; in the nucleus are its chromosomes, 48 in a human germ cell; and in the chromosomes are the genes. “ ATOAIS OF HEREDITY.” The genes have been called the atoms of heredity, but, as nobody has ever examined a gene or will ever be able to see it, the only thing we need say about them is that they are immeasurably smaller than the protein molecule which Dr Stanley has extracted from the tobacco leaf virus. The question which therefore arises is whether these crystals are really the virus, or whether the virus merely clingt to them. We are somewhere near the old quandary about living and non-living matter with which we began, though hero tho answer seems rather clearer. Dr Stanley’s belief that the crystals are tho virus cannot be disproved, but his conclusions leave more than one doubt. Why should a ■ dead protein molecule acting on other molecules stir them up to produce poison ? Or why should it give the appearance of life to them, or itself have that appearance? In a word the supposition does not make sense, whereas the activities of a living virus are perfectly clear and reasonable. It is an intensely parasitic living thing, unable to live outside tho cells of its host. From those cells it draws its sustenance, ami the food on which it is thus enabled to live has to undergo some unknown alteration to fit it for the virus's consumption. But none of these considerations affects the status of the virus as a living organised unit of life, ft has its own individuality, au individuality which cannot be probed to yield up the secret of its being and its actions. It lives, and no examination of it takes us nearer the origin of life. That is a. secret still.