Plant cyclotides: A unique family of cyclic and knotted proteins that defines the cyclic cystine knot structural motif.

@article{Craik1999PlantCA,
  title={Plant cyclotides: A unique family of cyclic and knotted proteins that defines the cyclic cystine knot structural motif.},
  author={David J. Craik and Norelle L. Daly and Trudy Bond and Clement Waine},
  journal={Journal of molecular biology},
  year={1999},
  volume={294 5},
  pages={
          1327-36
        }
}
Several macrocyclic peptides ( approximately 30 amino acids), with diverse biological activities, have been isolated from the Rubiaceae and Violaceae plant families over recent years. We have significantly expanded the range of known macrocyclic peptides with the discovery of 16 novel peptides from extracts of Viola hederaceae, Viola odorata and Oldenlandia affinis. The Viola plants had not previously been examined for these peptides and thus represent novel species in which these unusual… 
Discovery and structures of the cyclotides: novel macrocyclic peptides from plants
TLDR
The cyclotides have a diverse range of biological applications, ranging from uterotonic action, to anti-HIV and neurotensin antagonism, and have a range of potential applications as a stable peptide framework.
A novel suite of cyclotides from Viola odorata: sequence variation and the implications for structure, function and stability.
TLDR
This study confirms that cyclotides may be regarded as a natural combinatorial template that displays a variety of peptide epitopes most likely targeted to a range of plant pests and pathogens.
A novel suite of cyclotides from Viola odorata: sequence variation and the implications for structure, function and stability
TLDR
This study confirms that cyclotides may be regarded as a natural combinatorial template that displays a variety of peptide epitopes most likely targeted to a range of plant pests and pathogens.
Biosynthesis and insecticidal properties of plant cyclotides: The cyclic knotted proteins from Oldenlandia affinis
TLDR
A potent inhibitory effect on the growth and development of larvae from the Lepidopteran species Helicoverpa punctigera is described, indicating that the cyclotide domains are excised and cyclized from all four predicted precursor proteins.
The cyclotide family of circular miniproteins: nature's combinatorial peptide template.
TLDR
This review focuses on the structural aspects of cyclotides, which may be thought of as a natural combinatorial peptide template in which a wide range of amino acids is displayed on a compact molecular core made up of the cyclic cystine knot structural motif.
Natural structural diversity within a conserved cyclic peptide scaffold
TLDR
Although most have a similar backbone framework with a single disulfide bond and in many cases a head-to-tail cyclized backbone, they all have their own characteristics in terms of projections of side-chains, flexibility and physiochemical properties, attributed to the variety of their sequences.
Kalata B8, a novel antiviral circular protein, exhibits conformational flexibility in the cystine knot motif.
TLDR
The three-dimensional structure of kalata B8 is determined and broadening of resonances directly involved in the cystine knot motif is observed, suggesting flexibility in this region despite it being the core structural element of the cyclotides.
Diversity in the disulfide folding pathways of cystine knot peptides
TLDR
This work has examined the oxidative refolding and reductive unfolding of the prototypic member of the cyclotide family, kalata B1, suggesting that the circular backbone has a significant influence in directing the folding pathway.
Structural and biochemical characteristics of the cyclotide kalata B5 from Oldenlandia affinis.
TLDR
The expression, three-dimensional structure, and hemolytic activity of the cyclotide kalata B5 from the African plant Oldenlandia affinis is characterized and suggestions that this hydrophobic patch is a key feature for membrane binding and biological activity of cyclotides are supported.
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TLDR
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