Download A1989U926500001

_This Week’s Citation Classic________
Ghuysen J-NI. Use of bacteriolytic enzymes in determination of wall structure and their
role in cell metabolism. Bacteriol. Rev. 32:425-64. [968.
[Service de Bacteriologic. Universitd de Liege, Betgtum(
The bacterial wall peptidogivcao 5 a network structure. Clvcart strands of alternate 3,1-4 linked N-acetvlglucosamine and N-acetvlmuramic acid pyranoside
residues are substituted through the D-lacrvl group of
N-acetvlmuramic acid by L-Ala--y-D-Glu-L-Xaa -D-Ala
peptide units where L-Xaa is most often a diamino
acid, occasionally a neutral3amino acid. Peptide units
substituting adjacent glvcan strands are linked
together by means of bridges that involve the carbosyl
group of the terminal D-AIa of one peptide and either
the w-arnirio group or the diamino acid 1-Xaa or the
3 Deo-carboxyl group of D-Glu of another peptide.
pending on the composition and location of the
bridges, the wall peptidoglycans fall into four main
chemotvpes. [The SC/c indicates that this paper has
bew~cited in over 435 publications.j
tegritv of the wall whose essential function was to
keep the bacteria alive under usual environmental
conditions.
I became aware or these studies when, after receiving my PhD in physical chemistry at the University of Liege, I came to Maurice Welsch’s laboratory
at the medical school, a place known for its contributions to the concept of antibiosis. Welsch had obtained from the culture filtrate of Streptomycesaibus
a crude preparation called actinomycetin, which
had bacteriolytic activities. He was convinced that
the lytic agent was of enzymatic nature, but his at.
tempts to isolate it had failed. He probably thought
that I might have better luck.
I met Salton for the first time at the third International Congress of Biochemistry in Brussels, in 1955,
and the following year I worked for a few months
in his laboratory at the University of Manchester,
England. We found that, in marked contrast to lysozyme, the wall-degrading activity of two fractions
that I had laboriously isolated from actinomycetin
was attributable to distinct peptidases. The data were
illuminating. Possessing the right assortment of hy.
drolases should make it possible to establish the
The Rigid Matrix of Bacterial Cell Walls
structure of the bacterial cell walls by controlled and
progressive degradations.
I took about 12 years to carry the project to real
lean-Marie Ghuysen
Department of Microbiology
achievement. Original hydrolases, each of them hy.
drolysing specific linkages, were isolated and used
University of Liege
8-4000 Liege
to dismantle, in an ordered manner, the walls of
Belgium
various types of bacteria into increasingly smaller
fragments. The fragments were isolated, their
structure was established, and the “puzzle” was reconstituted, giving rise to the concept of the wall
March 14, 1989
peptidoglycan, a term that, following a roundtable
discussion that took place in Detroit, l used for the
first time in one of my “biochemistry” papers pubIn the early 1950s, the bacterial cell wall had lished in 1966.
I believe that the popularity of the article was due
emerged as a new field of research. Milton R.J. Salton
had succeeded in isolating the walls of several types to the unified view it presented. Despite endless variof bacteria, the first analyses of which had revealed ations in the primary structure, all the bacterial wall
the occurrence ofcompounds that had never before peptidoglycans are built on the same general pattern.
been encountered in nature. Claes Weibull had ob- Simplicity had emerged from a seemingly inextricaserved that, upon treatment with lysozyme, resting ble complexity.
celIs of Bacillus megaterium were transtormed into
One of the bacteriolytic enzymes described in the
wall-less, fragile protoplasts, and loshua Lederberg article was in fact a OD-carboxypeptidase. This
had seen that cells of Escherichia coil growing in a enzyme catalysed an important shift in my research
hypertonic medium were changed into fragile spher- and that of my associates as we became interested
ical cells when penicillin was added to the culture. in a detailed study of2 this penicillin-resistant metallo
Though the underlying mechanisms were different, (Zn) DO-peptidas&- of the serine DD-peptidases,
lysozvme and penicillin brought about a loss of in. penicillin-binding proteins, and 3.lactamases.M
I. Dideberg 0, Charlier P. Dive G. ions B, Frhre i-sI & Ghuysen i-NI. Structure at 2.5 A resolution of a
Zn -conraining D-alanvi-O-alanine-cleaving cath pcptidase. Sort/re 299:469-70. 1982. Cited 30 lImes.)
2. KelI~.1 A. Dideberg 0. Charlier P. Wfrv J P. Libert 5NI. Nloewn P C. Knox J R, Duet C. Fruipont C, ions B,
Dusart i, Frere J-M & Ghuysen i-NI. On the ongin of bacterial resistance to penicillin. Comparison of a
3-lactamase and a penicillin target. Science 231: 429-37. 986. iCited 40 times.)
3. Duen C, Piron-Fraipont C. ions B. Dusant i. CriSes NI S. Martini i A. Frere .1-NI & Ghuysen I-NI. Primary structure
of the Strepromyc-es 561 extraceliular DD-peptidase. I. Cloning into Srrepromvces lii’idans and nacleotide sequence of
he gene. Eur. I. Biochem. 162:509-18. 987.
4. Dideberg 0. Chanlier P. Wery J P. Dehottap P. Dusant i. Erpicum 1, Frère i-Nt & Ghuysen i.M, The crystal
structure of the 5-laccamase of Steepromvcss aibus G at 0.3 ron resolution. Biochemical 3, 245:911-3, 987,
5. ions B. Ghuvseni-Nt. Dive 6. Renard A. Dideberg 0. Charlier P. Frhre i-Nt. KeII~J A, Bovington J C.
\Ioews P C & Knox J R, The .,crivc-,ite-ser4i: ~.,,s’~iiin.recoCotzinoenzymes as members of the Streprornrvvs 561
OD-peptidase family. Bioc’hem,c’ai J. 250:313-24. 988.
6. Ghuvsen i-NI. Bacterial active-rite serine penicillin-intrractive proteins and domains: mechanism, structure, and evolution.
Re,’ tnt5c. Oh. 0:726-32. 1988.
CURRENT CONTENTS®
cc ,/~
©1989 by [SI®
IS, V. 32, p23, June 5, 1989
17