Advances in Enzymology and Related Areas of Molecular Biology, Volume 36

374 Pages·1972·14.343 MB·English

ADVANCES IN
ENZYMOLOGY
AND RELATED AREAS OF
MOLECULAR BIOLOGY
Volume 36
CONTRIBUTORS TO VOLUME 36
ERNESTB OREKD, epartnierit of Microbiology, University of Colorado Medical Center,
Denver, Colorado
PEDROC UATRECASDAiSv,i sion of Clinical Pharrnacology, TheJohns Hopkins University
School of Medicine, Baltirnorc, Maryland
P. M. DEYD, epartnrertt ofBiochernistry, Royal Holloway College (University of London),
Englefield Green, Surrey, England
VICTOR GINSBURGDe, partiwent of Health, Edirration and Welfare, National Institutes of
Health, Public Health Service, Bethesda, Maryland
FREDERICGKR INNELLB,i ochemistry Research Section, Veterans Administration Hospital,
Dallas, Texas
SYLVIAJ. KERRD, cyartinent of Surgery, University of Colorado Medical Center, Denver,
Colorado
G. A. LEVVYE, nzymology Department, Rowett Research Institute, Bucksburn, Aberdeen,
Scotland
JONATHASN. NISHIMUDReApar,t rriciit ofBioihernistry, The Uiiiversity of Texas Medical
School, Sari Antonio, Texas
DAVIDJ . PRESCOTBTr,y ir Mawr College, Departnicnt of Biology, Bryn Mawr, Penn-
s ylvartia
J. B. PRIDHAMD,e partment of Biochernistry, Royal Hollotuay College (University of
London), Englefield Green, Surrey, England
SYBILM . SNAITH,E nzymology Departniertt, Roivett Research Institute, Bucksburn,
Aberdeen, Scotland
CELIAW HITET ABORLa,b oratory of Biochemical Pharmacology, National Institutes of
Health, National Institute of Arthritis arid Metabolic Diseases, Bethesda, Maryland
HERBERTTA BORL,a boratory of Biocherirical Pharmacology, National Institutes of Health,
National Institute of Arthritis and Metabolic Diseases, Bethesda, Maryland
P. ROY VAGELODS,e partment ofBiologica1 Chemistry, Washington Uriiversity School of
Medicine, St. Louis, Missouri
ADVANCES IN ENZYMOLOGY
AND RELATED AREAS OF MOLECULAR BIOLOGY
Founded by E. F. NORD
Edited by ALTON MEISTER
CORNELL UNIVERSITY MEDICAL COLLEGE, NEW YORK
VOLUME 36
1972
INTERSCIENCE PUBLISHERS
a Division of JOHN WILEY & SONS
. .
New York London Sydney Toronto
Copyright 0 1972, by John Wiley & Sons, Inc.
All rights reserved. Published simultaneously in Canada.
No part of this book may be reproduced by any means, nor
transmitted, nor translated into a machine language with-
out the written permission of the publisher.
Library of Congress Catalog Card Number: 41-9213
ISBN 0-471-59171-8
Printed in the United States of America.
10 9 8 7 6 5 4 3 2 1
CONTENTS
The tRNA Methyltransferases
. . . . . .
By Sylvia J. Kerr and Ernest Borek 1
Affinity Chromatography of Macromolecules
By Pedro Cuatrecasas . . . . . . . . . . 29
Biochemistry of cr-Galactosidases
By P. M. Dey and J. B. Pridham . . . . . . 91
Enzymatic Basis for Blood Groups in Man
By Victor Ginsburg . . . . . . . . . . 1 31
The Inhibition of Glycosidases by Aldonolactones
By G. A. Levvy and Sybil M.S naith . . . . . . 1 51
Mechanism of Action and Other Properties of Succinyl Coenzyme
A Synthetase
By Jonathan 8. Nishimura and Frederick Grinnell . . 183
Biosynthesis and Metabolism of 1,4-Diaminobutane, Spermidine,
Spermine, and Related Amines
. . . .
By Herbert Tabor and Celia White Tabor 203
Acyl Carrier Protein
By David J. Prescott and P. Roy Vagelos . . . . 2 69
AuthorIndex . . . . . . . . . . . . . . . 3 13
Subject Index . . . . . . . . . . . . . . . 3 39
Cumulative Indexes, Volumes 1-36 . . . . . . . . 3 49
ADVANCES IN ENZYMOLOGY
AND RELATED AREAS OF
MOLECULAR BIOLOGY
Volume 36
Advances in Enzymology and Related Areas ofMolecular Biology, Volume 36
Edited by F. F. Nord
Copyright © 1972 by John Wiley & Sons, Inc.
THE tRNA METHYLTRANSFERASES
By SYLVIA J. KERR AKD ERNEST BOREK, Denver,
Colorado
CONTENTS
I. Introduction 1
11. Genetics 4
III. Interaction of S-Adenosylmethionine and Methyltransferases 6
IV. Recognition Sites of the tRNA Rlethyltransferasos 9
V. Ontogenetic and Organ 8pecificit.y of the tRNA Methyltransferases 13
VI. Modulation of the tRNA Methyltransferases in Various Biological
Systems 16
A. Bacteriophage Induction and Infection 16
B. Nononcogenic and Oncogenic Virus Infection 16
C. Hormone-Induced Modification of the tRNA Met.hyltransferases 17
VII. Inhibitors of the tRNA Methyltransferases 19
A. Naturally Occurring Inhibitors 19
Synthetic Inhibitors 21
11.
VIII. Stimulation of the tRNA Methyltransferases 21
IX. Other Modifications of tRNA 22
X. Summary 24
References 24
I. Introduction
The transfer RNA methyltransferases, a family of enzymes that
methylate transfer RNA at the macromolecular level, have been
adequately reviewed up to 1967 (1,2,3). Therefore, our review will
concentrate on publications and information that have emerged since
then.
After the discovery of methyl-deficient tRNA by the finding that
synthesis of the polynucleotide chain and methylation are sequential
reactions and these reactions can bc separated in a “relaxed” organism
of Escherichia coli, several groups of investigators studied the behavior
of methyl-deficient transfer RNA in certain in vitro furictional tests.
Essentially, no differences were found betwecn methyl-deficient transfer
1
2 SYLVIA J. KERR AND ERNEST BOREK
RNA and the species normally endowed with the appropriate methyl
groups. The reason for this is at least twofold. The first one is obvious:
the methyl-deficient transfer RNA, as it was available then, consisted
of an almost equal mixture of methyl-free and completely methylated
RNAs. This is inherent in the method of synthesis of methyl-deficient
tRNA. Prior to starvation of methionine, the organisms must be
grown to a high population in presence of the amino acid; during
growth they synthesize tRNA, which is normally methylated and
remains stable during the starvation.
The second reason for the failure to detect any changes, especially
in the transfer function to the ribosomes, is that methylation is not
the only modification of transfer RNA. More recent work has resolved
some of these problems. In thc first place, apparently completely
methyl-free tRNA is available from the very skillful large scale separa-
tions performed at Oak Ridge Laboratories. Novelli and his co-
workers were able to show that in methyl-free transfer RNA
(4)
acceptance of amino acids is at a coiisiderably lower rate than that in
normal transfer RNA.
The modified bases involved in the recognition of the interaction
between activating enzymes and tRNA have not been identified at the
present time. However, in the case of the transfer function to ribo-
somes, there is a well-defined, absolute requirement. In all transfer
RNAs except tRNAf’llet, the base adjacent to the anticodon at the
3’ position is modified. It has been shown in thrce different cases (5,6,7)
that if the modification of the base next to the anticodon is lacking,
then the tRKA, while it still accepts its appropriate amino acid, will
no longer be able to transfer it to the ribosomes. Gefter and Russell (5)
studied the suppressor tRKA‘rYrp roduced in E. coli by the transducing
phage derived from phage $80. This tRNA has an adenine next to its
anticodon that is triply modified. It contains an isopentenyl group
in the N6 position and a niethylthio group in the 2 position (at least
three different enzymes must achieve these modifications.) After
infection, the extent of these modifications can be controlled by cultural
conditions. If all of the modifications are lacking, the inability to
attach to ribosomes is absolute. If it is partially modified, the ribo-
somal attachment, is only partially suppressed. Thiebe and Zachau (6)
have studied tRNA’”e yeast which has the modified base Y next to its
anticodon. If this base is excised by exposure to mild acid, the ability
of the tRNA for ribosomal attachment disappears.
THE tRNA METHYLTRANSFERASES 3
The effect of the removal of the modification of still another anti-
codon-neighboring base is one studied by Fittler and Hall (7). They
removed the isopentenyl moiety from tRNA by oxidation with perman-
ganate. The tRNA was still functional in the amino acid charging
reaction, but the ribosomal attachment function was eliminated.
It is obvious from these examples that any in vitro study of methyl-
deficient tRNA in its ribosomal transfer function would be meaningless
if the modification of the anticodon-neighboring base were other than
methylation.
It has also been shown in Peterkofsky's laboratory (8) that with
methyl-deficient tRNA the codon response is different from the codon
response of the normal species. Therefore, at least three functions of
the modifications of tRNA have emerged in the recent past. The
answer to what other functions they may have awaits the availability
of transfer RNAs with specific modifications missing from known
positions. However, even with such products, great care will have to
be taken in the interpretation of findings. Should any of these modifi-
cations have a role in regulation, then in vitro assays may fail to reveal
such a mechanism. The above observations provide partial confirma-
tion for the hypothesis proposed some years ago that the modifications
of tRNA are required for protein synthesis (9).
Two model tRNAs may be available for studying the role of specific
modifications on the structure and function of tRNA. The first of
these would be tRNA*" transcribed from the gene synthesized by
Khorana and his eo-workers (lo).
Another such model, a biological one, turned up unexpectedly in
Strominger's hands during his monumental studies on the mechanism
of cell wall synthesis. Among the populations of tRXAs extracted
from Staphyloccoccus epidermis, Strominger and his group have isolated
a tRNAGIPt hat can be charged by the mixture of charging enzymes in
this organism and participates in in vitro peptidoglycan synthesis but is
totally inert in in vitro protein synthesis (11,12). Analysis of this
purified tRNAGlYr evealed that it contains but one modified base,
4-thiouridine (12). The whole coterie of the other modified bases,
dihydrouridine, pseudouridine, and all of the methylated bases are
absent from its structure. Physicochemical studies of this substrate
should yield highly valuable information on the role of modifications in
determining the secondary and tertiary structure of tRNA.
Another intriguing question that may be answered by the structure
4 SYLVIA J. KEHK AND EHNEST UOlIEK
of this unique tRNA IS hou it resists modification by the varicty of
enzymes Strominger suggests that perhaps it is an adventitious placing
of the thio group in the chain v hich prevents furthcr modification.
This is a plausible hypothesis, for some of the modifications of tRNAs
are knovn to be incorporated into tRNA before its mcthylation (13).
Another example of sequential modification is providrd from orli
H
in Brenner’s laboratory. The su tRNATbrd iscussed above has three
modifications on the adenine residue adjacent to the anticodon.
Three different enzymes arc needed for the modification of this base,
and they apparently react in the follon ing order. One enzyme intro-
duces the isopentenyl group; another enzyme introduces the sulfur
group; and finally still another enzyme methylates the thio group (14).
All other modifications of this tRNA molecule apparently occur prior
to the modifications of the base adjacent to the anticodon.
A structural modification that methylation is linown to confer on
tRNA is a hypochromic effect, hich implies an increment in secondary
u
and/or tertiary structuring. This has becn shown both by enzymatic
methylation of methyl-deficient tRNd from E. coli by its homologous
enzymes (15), as me11 as by chemical methylation (16).*
At any rate, one might safely retract now what was said a few years
ago, that the “tRNA methyltransferases are enzymes in search of a
function.”
11. Genetics
Very interesting studies on the genetic origiiis of the tRNA methyl-
transferases have come from the groups studying these enzymes at
Uppsala. Kjellin-Straby and Boman (18) observed that a methionine
auxotroph of Xaccharoinyces cerwisiae accumulates partially methyl-
deficient RKA during methionine deprivation. In an extension of
these observations Kjellin-Straby and Phillips studied a number of
other methionine auxotrophs of yeast. Among these they found a
mutant which lacks in its tRKA 2V2-dimethyl guanine (19). That this
deficiency is due to the lack of the appropriate enzyme, rather than to
some change in the tRNA sequence, was unequivocally demonstrated
*
For an outstanding review of the tertiary stiucturc of tRKA read Cramer(l7).
Structural interrelationships that are baffling on the basis of the two-dimensional
cloverleaf model become obvious when eoiisitleiecl on the basis of Cramer’s
model of the intricate trrtiary structurc of tRNA.