Barley
Stripe
Mosaic
Virus
-
BSMV - BSMV is a rigid helical plant virus 130 nm long and 30 nm wide.
Three types of particles have been reported, 111 nm (180S), 128 nm (1898) and 148 nm (l99S).. The protein subunits are arranged in a helical manner. The pitch of the helix is 2.6 nm.
There
are,
probably
60
subunits
in
five
turns
of
the
helix.
The
central
cavity
of
the
particle
is
1.5-2.0
nm
in
diameter.
RNA
appears
to
be
located
at
a
radius
of
5.5
nm
from
the
long
axis
of
the
particle.
The
molecular
weight
of
the
protein
subunit
is
21,500,
corresponding
to
187-
190
amino
acid
residues.
The subunit appears to have little or no α helix. BSMV is a multicomponent virus, with some isolates having two and some three RNA species. Both or all three appear to be required for infectivity. Encapsulation of the genome of one virus in the capsid of another is called phenotypic mixing or genome masking. The
RNA
of
the
rod
shaped
BSMV
has
been
encapsulated
in
the
capsid
of
the
icosahedral
brome
mosaic
virus,
and
the
RNA
of
the
rod
shaped
TMV
in
the
capsid
of
BSMV.
