2 research outputs found
Potential use of a group II alphabaculovirus isolated from <i>Mamestra brassicae</i> as a broad-spectrum biological pesticide
<p>A novel native isolate of <i>Mamestra brassicae</i> nucleopolyhedrovirus, designated MabrNPV-CHb1, was identified in this study. The complete nucleotide sequence of MabrNPV-CHb1 was determined. The MabrNPV-CHb1 genome consists of 154,451 bp, with a G + C content of 40.05%. The genomic sequence and comparative analysis indicated that MabrNPV-CHb1 shares high nucleotide identity with MabrNPV-K1, HearMNPV, MacoNPV-B and MacoNPV-A. The major difference between MabrNPV-CHb1 and MabrNPV-K1 is the absence of MabrNPV-CHb1 ORF134 in MabrNPV-K1. The MabrNPV-CHb1 ORF134 is a gene encoding a putative transposase, and phylogenetic analysis suggests that it is derived through horizontal gene transfer (HGT) from ascoviruses. MabrNPV-CHb1 exhibits broad-spectrum activity against lepidopteran agricultural pests, including insects in the families Noctuidae and Plutellidae. A high yield of MabrNPV-CHb1 occlusion bodies was obtained by propagation in alternative hosts, demonstrating its potential for pesticide application. Its broad host range, high yields in alternative hosts and clear genetic background could extend its potential applications as a broad-spectrum insecticide in the future.</p
Supramolecular Cross-Linking and Gelation of Conjugated Polycarbazoles via Hydrogen Bond Assisted Molecular Tweezer/Guest Complexation
Supramolecular cross-linking and
gelation represent a fascinating
approach to improve the performance of π-conjugated polymers.
Up to now, supramolecular π-conjugated polymer networks have
been mainly developed by grafting noncovalent recognition motifs onto
the side-chain of π-conjugated polymers. In comparison, much
less attention has been paid to the construction of main-chain-type
supramolecular polymer networks, in which π-conjugated polymers
themselves serve as the noncovalent linkages. Herein we have developed
a novel and efficient strategy to attain this objective. The design
principle is primarily on the basis of noncovalent molecular recognition
between bisÂ[alkynylÂplatinumÂ(II)]Âterpyridine molecular
tweezer receptor and <i>NH</i>-type carbazole guest, which
shows enhanced binding affinity due to the cooperative participation
of donor–acceptor and intermolecular N–H---N hydrogen-bonding
interactions. The “hydrogen-bond enhanced molecular tweezer/guest
recognition” strategy can be further applied for multivalent
complexation between π-conjugated polycarbazoles and homoditopic
molecular tweezer cross-linker, leading to the formation of main-chain-type
supramolecular polymer networks and gels with thermal and solvent
responsiveness. Hence, π-conjugated polymers can be endowed
with excellent processability via the supramolecular engineering approach,
which provides a new avenue toward flexible optoelectronic applications