288
D. J. BELL
Foreword
The aim of this chapter is to present to those interested in the comparative aspects of biochemical knowledge: (i) a general account of
the structures of the monosaccharides, both as interrelated free chemical individuals and as units out of which more complex natural molecules are wholly or partly constructed; and (ii) a report on the natural
distribution of the monosaccharides, both in the free state and in
chemical combinations.
The writer makes no claim to infallibility; much important and interesting information must undoubtedly have been overlooked. Since
the advent of methods of isolation and separation of sugars based on
column and partition chromatography and on electrophoresis, the flow
of publications relating to carbohydrate biochemistry has become magnified from the placid stream of the 1930's to the tumultuous torrent of
the 1950's. When in the early 1930's the writer was a student of carbohydrate chemistry, natural monosaccharides could be roughly numbered
as about twenty; in the early months of 1960 the reader will see how
this family has increased manyfold. In his early days the writer was
told by some of his seniors—working in other subjects, however—that
he would be ill-advised to pursue the study of carbohydrates "as the
field had now been fully worked out"!
When endeavoring to plan this chapter two lines of approach presented themselves. The one was to treat the subject from the basis of
occurrence of sugars according to phyla, genera, etc.; the other was to
base divisions and subdivisions on the sugars themselves. It very soon
became apparent that the second alternative was the only one possible
since enormous lacunae exist in our knowledge of the presence of
chemical substances in even closely related species. This field presents
enormous opportunities for work with animals, plants, and microorganisms, especially in relation to genetics. In connection with the latter
approach, the human familial conditions of L-xylulosuria, D-galactosemia,
and the glycogen storage diseases may be recalled.
The physiological roles of many of the natural simple sugars and
their derivatives are quite unknown and present the biologist with another vista of unexplored science. The field can hardly be said, nowadays, to have been worked out.
The reader may object that certain substances obviously derived
from carbohydrates are not included in this chapter. The sialic acids,
muramic acid, and sugar oxo acids are conspicuous examples. The
writer humbly pleads that, although asked by the Editors to cast his
D. J. BELL
Foreword
The aim of this chapter is to present to those interested in the comparative aspects of biochemical knowledge: (i) a general account of
the structures of the monosaccharides, both as interrelated free chemical individuals and as units out of which more complex natural molecules are wholly or partly constructed; and (ii) a report on the natural
distribution of the monosaccharides, both in the free state and in
chemical combinations.
The writer makes no claim to infallibility; much important and interesting information must undoubtedly have been overlooked. Since
the advent of methods of isolation and separation of sugars based on
column and partition chromatography and on electrophoresis, the flow
of publications relating to carbohydrate biochemistry has become magnified from the placid stream of the 1930's to the tumultuous torrent of
the 1950's. When in the early 1930's the writer was a student of carbohydrate chemistry, natural monosaccharides could be roughly numbered
as about twenty; in the early months of 1960 the reader will see how
this family has increased manyfold. In his early days the writer was
told by some of his seniors—working in other subjects, however—that
he would be ill-advised to pursue the study of carbohydrates "as the
field had now been fully worked out"!
When endeavoring to plan this chapter two lines of approach presented themselves. The one was to treat the subject from the basis of
occurrence of sugars according to phyla, genera, etc.; the other was to
base divisions and subdivisions on the sugars themselves. It very soon
became apparent that the second alternative was the only one possible
since enormous lacunae exist in our knowledge of the presence of
chemical substances in even closely related species. This field presents
enormous opportunities for work with animals, plants, and microorganisms, especially in relation to genetics. In connection with the latter
approach, the human familial conditions of L-xylulosuria, D-galactosemia,
and the glycogen storage diseases may be recalled.
The physiological roles of many of the natural simple sugars and
their derivatives are quite unknown and present the biologist with another vista of unexplored science. The field can hardly be said, nowadays, to have been worked out.
The reader may object that certain substances obviously derived
from carbohydrates are not included in this chapter. The sialic acids,
muramic acid, and sugar oxo acids are conspicuous examples. The
writer humbly pleads that, although asked by the Editors to cast his