Biology Reference
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Fig. 6.
Dissection of IMV. (
a, b
) Treatment of non-ionic detergent (1%
Igepal) in combination with a reducing agent (2% 2-mercaptoethanol) for
30-45 min at 37ºC leads to separation of core envelopes (
a
) and virion cores
(
b
). (
c
) Extended treatment (120-180 min) with the same combination
leads to the unfolding of the virion cores, leading to 30-40 nm-diameter
tubules (arrow). (
d, e
) Further dissection using proteinase K at 37ºC for
90-180 min results in the appearance of the 16 nm-diameter segmented
tubules (
d
) and residual tubular segments, either isolated or associated with
DNA strands (white arrows in (
e, f
)).
lacking a 30 nm thick envelope. As seen in Fig. 6b, many viral cores
possess satellite domains. These satellite domains may correspond to
the lateral bodies observed in conventional EM images.
17
Prolonged treatment of IMV viruses with non-ionic detergent
plus reducing agent produces complete unfolding of IMV and the
emergence of 30-40 nm diameter tubules as seen in Fig. 6c. On these
tubules, a helical array of protein subunits with left-handed helicity
and a pitch of approximately 16 nm is evident. Treatment with high
proteinase K concentrations plus SDS results in the same 30-40 nm
