Insect Biochemistry and Function

318 Pages·1975·6.14 MB·English

by  B. Sacktor (auth.)

Insect Biochemistry
and Function
Insect Biochemistry
and Function
Edited by
0.1. CANDY
Lecturer in Biochemistry
University of Birmingham
and
B. A. KILBY
Reader in Biochemistry
University of Leeds
CHAPMAN AND HALL
LONDON
First published 1975
by Chapman and Hall Ltd
11 New Fetter Lane, London EC4P 4EE
First published as a Science Paperback 1978
© 1975 Chapman and Hall Ltd
Typeset by Preface Limited, Salisbury, Wilts
ISBN-13: 978-0-412-21530-8 e-ISBN-13: 978-94-009-5853-1
DOl: 10.1007/978-94-009-5853-1
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Distributed in the U.S.A. by Halsted Press,
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Contributors
E. Bailey Dept: of Biochemistry, The University, Sheffield,
Yorkshire.
D. G. Cochran Dept: of Entomology, Virginia Polytechnic, Insti
tute and State University, Virginia, U.S.A.
G. G. Lunt Dept: of Biochemistry, School of Biological
Sciences, University of Bath, Somerset.
B. Sacktor Gerontology Research Center, National Institute of
Child Health and Human Development, National In
stitute of Health, Baltimore, U.S.A.
Contents
Page
Preface xi
Chapter 1. Biochemistry ofInsect Flight. B. SACKTOR
Part 1 - Utilization of Fuels by Muscle 1
In trod uction 3
Pathways for the Utilization of Carbohydrates, Amino acids
and Fats in Flight Muscle 4
Physiological aspects of the bioenergetics of flight 4
Glycogenolysis 5
Utilization of trehalose 20
Glyco!ysis 22
Glycolytic-mitochondrial interactions 29
Auxiliary glycolytic reactions 33
Oxidation of the end-products of glycolysis and the
permeability of mitochondria to metabolic intermediates 35
Utilization of amino acids 40
Oxidation of fat 45
The Control of Flight Muscle Mitochondrial Metabolism 49
Morphological and biochemical organization of flight
muscle mitochondria 50
Oxidative phosphorylation 56
Control of the mitochondrial oxidation of a-glycerol-P 61
Control of the mitochondrial oxidation of proline 63
Control of the mitochondrial oxidation of pyruvate and
the citric acid cycle 65
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viii INSECT BIOCHEMISTRY AND FUNCTION
Mitochondrial ion movements and the special role of Ca2+
in the regulation of flight muscle metabolism 70
The oxidation-reduction state of the respiratory
components in mitochondria and the control of
me tabolism 76
References 81
Chapter 2. Biochemistry of Insect Flight. E. BAILEY
Part 2 - Fuel Supply 89
Introduction 91
The Nature of Respiratory Fuels 92
Stores of Respiratory Fuels 93
Lipids and their Metabolism 94
Tissue content of lipids 96
Absorption of dietary lipids and incorporation into fat
body lipids 107
Lipid degradation by fat body 110
Biosynthesis of lipids 117
Lipid release from the fat body 137
Carbohydrates and their Metabolism 146
Tissue content of carbohydrates 146
Utilization of carbohydrate reserves during flight 148
Metabolism of sugars other than glucose 150
Glycogen biosynthesis 152
Trehalose biosynthesis 154
Carbohydrate synthesis from non-carbohydrate
precursors 157
Glycogen breakdown 159
Hormonal control of carbohydrate metabolism 161
The Supply of Amino Acid Fuels for Flight 164
Conclusion 166
References 167
Chapter 3. Excretion in Insects. D. G. COCHRAN 177
Introduction 179
Excretion Associated with the Ma1pighian Tubule-Rectum
System 181
Ions, water and active transport 182
Uric acid 191
Ammonia 215
Urea 223
Amino acids 228
CONThNTS ix
Tryptophan derivatives 232
Pteridines 243
Other nitrogenous products 252
Carbohydrates 254
Miscellaneous excretory products 255
Xenobiotics 256
Minor Excretory Systems 258
Labial glands 259
Pericardial and other cells 260
Utriculi majores 261
The gut 262
Concluding Remarks 264
References 265
Addendum 282
Chapter 4. Synaptic Transmission in Insects. G. G. LUNT 283
Introduction 285
General Outline of the Insect Nervous System 285
Chemical Transmitters in the Central Nervous System 288
Acetylcholine 288
Acetylcholine receptors 289
Glutamic acid and 'Y-amino butyric acid (GABA) 290
Biogenic amines 293
Chemical Transmitters at the Neuromuscular Junction 294
Glutamic acid 294
Glutamate receptor 297
Enzymes associated with the glutamate system 298
'Y-Amino butyric acid (GABA) 300
Biogenic amines 30 I
Summary 301
References 302
Addendum 305
Index 307
Preface
There has been a considerable upsurge in interest in insect bio
chemistry and physiology in recent years and this has been reflected
in a notable expansion in the number of original papers in this field.
Whereas insect physiology has tended to receive ample attention
from reviewers, the same has not always been true for the more
biochemical aspects of insect research. This book is a venture to help
redress the balance. No attempt has been made to cover all aspects of
insect biochemistry, but rather a few topics have been selected which
seemed to us to merit a review at the present time.
One reason for this increased interest in insect biochemistry is
perhaps the growing realization that insects can be very useful
organisms to act as model systems for the experimental study of
general biochemical principles. One remembers, for instance, that
Keilin's perceptive observations on the flight muscles of living bees
and wax moths led to his discovery of the cytochromes. The
fundamental unity of biochemistry has long been accepted as a
dogma by the faithful and the insect kingdom provides no exception
to it. The main biochemical processes in insects are being revealed as
essentially the same as in other life forms but, as so often found in
comparative biochemistry, there are interesting variations on the
central theme. Often by choosing an appropriate insect species, one
can find an example of a particular biochemical mechanism which
has been developed or modified to a considerable extent and the
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study of such a system may be most informative about general
biochemical mechanisms. It is this correlation between biochemical
specialization and physiological function that can make the subject
so fascinating. A good example of such a process is insect flight,
which clearly illustrates the numerous biochemical adaptations that
can occur concomitant with a specific function. A discussion of this
subject has been given particular attention in the first half of this
book.
Another reason for the increased activity in insect biochemistry is
an economic one. The production of insecticides is now a major
industry and one in which constant research for new products is
essential. Insects soon develop resistant strains under selection
pressure from the use of a particular insecticide and the development
of new ones is frequently required. One would hope that an
increased knowledge of insect biochemistry and physiology would
facilitate a rational approach to the development of new lethal agents
which interfere with the normal life processes in insects. The aim,
however, must be selective toxicity in which the agent is insect
specific while man, other animals and if possible, beneficial insects
are unaffected and unharmed. This selectivity would not be expected
if the insecticide interferes with some fundamental process common
to most organisms as happens, for instance, with the use of cyanide
to inhibit cytochrome oxidase. Rather, the ultimate target of the
insecticide must be some biochemical or physiological adaption or
modification which is essential for the insect but absent or
unimportant in the species which one does not wish to harm. A
detailed knowledge of biochemical differences between insects and
other life forms could have great potential and importance and we
hope that this book may perhaps serve to stimulate further interest
and research in these areas, and eventually assist in the rational
design of selective insecticides.
D. 1. C.
October 1974 B. A. K.