Gulland, John Masson

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Gulland, John Masson

(b. Edinburgh, Scotland, 14 October 1898; d. Goswick, England, 26 October 1947)

organic chemistry, biochemistry.

Gulland’s father was professor of medicine at Edinburgh University; his mother was the daughter of David Masson, professor of English literature at the same university. His own studies in chemistry at that university were interrupted by war service, and he graduated in 1921. At the universities of St. Andrews and Manchester he and Robert Robinson established the structures of an important group of alkaloids including morphine. From 1924 Gulland was at Oxford with W. H. Perkin, Jr., and worked on strychnine and brucine; but the routine or degradation and synthesis began to pall, and his interest turned to biochemical problems of wider significance. He is remembered mainly for his work on the chemistry of nucleic acids, for which he was elected a fellow of the Royal Society in 1945. He carried out this work at the Lister Institute of Preventive Medicine, London (1931–1936), and as professor of chemistry at University College, Nottingham (1936–1947).

Gulland was one of the first to use methods other than those of classical chemistry to study the structure of nucleic acids. In early work he showed spectroscopically that the pentose residue was attached to the 9 position rather than the 7 position in the purine nucleosides. Later, with Elisabeth Jackson (1938), he found that the enzymatic hydrolysis of ribonucleic acid (RNA) gave evidence that the RNA nucleosides, like those of deoxyribonucleic acid (DNA), were linked by phosphate ester groups through the 3’ and 5’ positions. Owing to the difficulty of preparing pure enzymes, such evidence was then regarded with suspicion, and there was subsequently much confusion about the nature of the internucleotide link in RNA. The role of cyclic phosphates in the hydrolysis of RNA was not understood until the 1950’s, when Gulland’s evidence for the 3′-5′ link in RNA was seen to be valid.

Electrometric titration of DNA, done with D. O. Jordan and H. F. W. Taylor (1947), proved the existence of the hydrogen bonding which was an essential feature of the famous “double helix” of J. D. Watson and Francis Crick (1953). An earlier type of helical structure put forward by Linus Pauling and E. J. Corey had envisaged the phosphate groups as closely packed inside a single helix, the bases projecting radially on the outside. The Watson-Crick structure, on the other hand, required that two helices be linked by hydrogen bonds between the base pairs adenine-thymine and guanine-cytosine.

Gulland and his co-workers found that the primary phosphoric acid groups of DNA were readily titratable and thus, as was later realized, were on the outside of the double helix. With D. O. Jordan and J. M. Creeth, Gulland showed that the amino and amido groups of the bases were titratable only after treatment at extreme acid or alkaline pH, that is, only after there had been a breakdown into smaller molecular units, as confirmed by a decrease in viscosity and disappearance of streaming birefringence (1947). Rosalind Franklin and Raymond Gosling used Gulland’s titrations as the main evidence in favor of the double helix, to which they had been led by their own crystallographic studies (1953).

The full solution of most of the problems tackled by Gulland was usually a little beyond the reach of the techniques of the day; he did not think that “easy” research was worth doing. His striking appearance, personal charm, and skill with words made him a memorable teacher. He died in a railway accident and was survived by his wife and two daughters.

BIBLIOGRAPHY

I. Original Works. There is a not quite complete bibliography of Gulland’s works in the obituary notice of the Royal Society, cited below. Among his earliest publications, written with R. Robinson, are “The Morphine Group. Part I. A Discussion of the Constitutional Problem,” in Journal of the Chemical Society, 123 (1923), 980: and “The Constitution of Codeine and Thebaine,” in Memories of the Manchester Literary and Philosophical Society, 69 (1924–1925). For his work on purine nucleosides see “Spectral Absorption of Methylated Xanthines and Constitution of the Purine Nucleosides,” in Nature, 132 (1933), 782, written with E. R. Holiday.

His papers on RNA nucleosides, written with Elisabeth M. Jackson, include “Phosphoesterases of Bone and Snake Venoms,” in Biochemical Journal, 32 (1938), 590–596; “5-Nucleotidase,” ibid 597–601; “The Constitution of Yeast Nucleic Add,” in Journal of the Chemical Society (1938), p. 1492; and “The Constitution of Yeast Ribonucleic Acid. Part III. The Nature of the Phosphatase-Resistant Group,” ibid, (l939), p. 1842.

For works on Gulland’s other researches, see “Some Aspects of the Chemistry of Nucleotides,” ibid. (1944), p.208; “Deoxypentose Nucleic Acids. Part II. Electrometric Titration of the Acidic and Basic Groups of the Deoxypentose Nucleic Acid of Calf Thymus,” ibid. (1947), p. 1131, written with D. O. Jordan and H. F. W. Taylor; and “Deoxypentose Nucleic Acids. Part III. Viscosity and Streaming Birefringence of Solutions of the Sodium Salt of the Deoxypentose Nucleic Acid of Calf Thymus,” ibid., p. 1141, written with J. M. Creeth and D. O. Jordan.

II. Secondary Literature. Obituaries by R. D. Haworth appeared in Obituary Notices of Fellows of the Royal Society of London, 6 , no. 17 (l948), 67–82, and in Journal of the Chemical Society (1948), pp. 1476–1482; the former has a portrait. See also J. W. Cook, in Nature, 160 (1947). 702–703.

For the significance of Gulland’s work on nucleic acids, see D. M. Brown and A. R. Todd, “Evidence on the Nature of the Chemical Bonds in Nucleic Acids,” in E. Chargaff and J. N. Davidson, eds., The Nucleic Acids, I (New York, 1955), 409–445; R. E. Franklin and R. G. Gosling, in Nature, 171 (1953), 740–741; D. O. Jordan, The Chemistry of nucleic Acids (London, 1960), pp. 67–68, 140–153, 169–170, and passim; and J. D. Watson, The Double Helix (London, 1968), p. 183.

Kathleen R. Farrar

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