Nucleic
Acids
Resea ch,
Vol.
19,
No.
6
1343
IS200
is
no
a
membe
o
he
1S600
amily
o
inse ion
sequences
Isid e
Gibe ,
Ka en
Ca oll1,
Da id
R.Hillya d',
Jo di
Ba be
and
Josep
Casadesus2*
Depa amen
de
Gene ica
i
Mic obiologia,
Uni e si a
Au onoma
de
Ba celona,
08193
Bella e a,
Ba celona,
Spain,
'Depa men
o
Pa hology,
Uni e si y
o
U ah,
Sal
Lake
Ci y,
UT
84112,
USA
and
2Depa amen o
de
Gen6 ica,
Uni e sidad
de
Se illa,
Apa ado
1095,
41080
Se ille,
Spain
Submi ed
Janua y
2,
1991
EMBL
accession
no.
X56834
IS200
is
an
inse ion
sequence
p esen
in
all
Salmonella
species
excep
S.
agona
(1, 2).
The
elemen
is
absen
om
all
o he
En e obac e iaceae,
wi h
he
excep ion
o
some
s ains
o
Shigella
lexne i
and
Shigella
sonnei
(2).
I
had
been
hypo hesized
ha
he
i s
mu a ion
cha ac e ized
as
an
IS200
inse ion,
hisD984:
:IS200
(1,
3)
migh
ac ually
be
a
dele ion
mu an
o
he
Shigella
inse ion
elemen
IS630
(4).
Howe e ,
sequencing
o
he
ends
o
a
second
mu a ion
caused
by
IS200
inse ion
la e
sugges ed
ha
IS200
was
a
dis inc
inse ion
elemen
(5).
We
ecen ly
ob ained
he
comple e
nucleo ide
sequence
o
he
inse ion
elemen
IS200
inse ed
in
he
his idine
ope on
o
S.
yphimu iwn
(causing
he
mu a ion
hisD984:
:IS200).
The
elemen
is
708
bp
long;
i
his
size
co esponds
o
a
wild- ype
elemen ,
IS200
can
be
conside ed
he
smalles
inse ion
sequence
known
(6).
A
diag am
o
he
hypo he ical
s uc u e
o
IS200
is
p esen ed
in
Figu e
1.
Unlike
many
inse ion
elemen s,
IS200
lacks
enninal
in e ed
epea s,
as
p e iously
epo ed
(3,
5).
The
elemen
con ains
h ee
po en ial
open
eading
ames
(ORF
1,
ORF
2
and
ORF
3),
whose
coding
capabili ies
a e
69,
71
and
58
amino
acids,
espec i ely.
ORF2
and
ORF3
a e
o e lapping;
he
exis ence
o
o e lapping
ORFs
is
no
su p ising,
since
i
seems
o
be
ex emely
common
among
bac e ial
inse ion
sequences
(6).
O he
in e es ing
ea u es
o
IS200
a e
he
ollowing:
(i)
Th ee
po en ial
hai pin
loops
a e
loca ed
nea
he
' igh '
end
o
he
elemen
(Figu e
1).
One
o
he
loops,
cen e ed
on
base
688,
s ongly
eminds
o
a
Rho-independen
ansc ip ion
e mina o ,
as
p e iously
sugges ed
(3).
Two
smalle
hai pins
a e
cen e ed
on
bases
608
and
665.
(ii)
Two
nea ly
pe ec
in e ed
epea s
o
20
bp
exis
wi hin
he
sequence.
Bo h
epea s
a e
loca ed
nea
he
' igh '
end,
ex ending
be ween
nucleo ides
565-584
and
629-648
(Figu e
1).
The
epea s
di e
by
only
4
misma ches
and
hei
po en ial
biological
signi icance
is
unknown.
A
sea ch
in
he
EMBL
da a
bank
has
con i med
ha
IS200
is
no
a
dele ion
mu an
o
IS630,
al hough
wo
disc e e
egions
o
homology
(8
and
10
bp
long)
appea
o
exis
be ween
IS200
and
IS630.
Likewise,
wo
sho
egions
o
homology
(7
and
8
bp
long)
a e
ound
be ween
IS200
and
he
Shigella
sonnei
inse ion
sequence
IS640.
Two
DNA
s e ches,
10
and
11
bp
long,
homologous
o
he
S.
sonnei
elemen
IS600
ha e
also
been
ound.
P obes
lacking
homology
wi h
he
Shigella
elemen s
IS600,
IS630
and
IS640
can
now
be
ob ained
by
cloning
speci ic,
in e nal
agmen s
o
IS200.
These
p obes
a e
expec ed
o
be
use ul
o
ind
ou
whe he
he
hybndiza ion
ound
be ween
IS200
p obes
and
ce ain
Shigella
DNAs
(2)
was
caused
o
no
by
c oss-
hyb idiza ion
be ween
IS200
and
Shigella
inse ion
elemen s.
ACKNOWLEDGMENTS
The
S.
yphimu ium
s ain
ca ying
he
mu a ion
hisD984:
:IS200
was
kindly
p o ided
by
John
R.Ro h.
We
a e
g a e ul
o
And 6s
Ga z6n
o
in e es ing
discussions
and
o
Ma en
Ma sh
o
help ul
assis ance.
REFERENCES
1.
Lam,S.
and
Ro h,J.R.
(1983)
Cell
34,
951-960.
2.
Gibe ,I.,
Ba be,J.
and
Casadesds,J.
(1990)
J.
Gen.
Mic obiol.
136,
2555-2560.
3.
Lam,S.
and
Ro h,J.R.
(1986)
J.
Mol.
Biol.
187,
157-167.
4.
Ma su ani,S.,
O hsubo,H.,
Maeda,Y.
and
O hsubo,E.
(1987).
J.
MoI.
Bio.
196,
445-455.
5.
O'Reilly,C.,
Black,G.W.,
La ey,R.
and
McConnell,D.J.
(1990).
J.
Bac e iol.
172,
6599-6601.
6.
Galas,D.J.
and
Chandle ,M.
(1989).
In
Be g,D.M.
and
Howe,M.M.
(eds)
Mobile
DNA.
Ame ican
Socie y
o
Mic obiology,
pp.
109-162.
EI
SIDE
1
920
SIDE
ORF2
ORF1
75
290
384
593
ORF
3
75
251
Figu e
1.
A
diag am
o
he
inse ion
hisD984::IS200.
The
o ien a ion
o
he
inse ion
elemen
in
he
hisD
gene
is
indica ed
by
he
'O'
and
'E'
sides.
Po en ial
ORFs,
hai pin
loops
and
in e nal
in e ed
epea s
a e
also
shown.
The
ela i e
sizes
o
he
hai pins
is
indica ed
(bu
no
d awn
o
scale).
*
To
whom
co espondence
should
be
add essed
.:)
1991
Ox o d
Uni e si y
P ess