1. Complex precursor structures of cytolytic cupiennins identified in spider venom gland transcriptomes
Lucia Kuhn-Nentwig Sci Rep. 2021 Feb 17;11(1):4009. doi: 10.1038/s41598-021-83624-z.
Analysis of spider venom gland transcriptomes focuses on the identification of possible neurotoxins, proteins and enzymes. Here, the first comprehensive transcriptome analysis of cupiennins, small linear cationic peptides, also known as cytolytic or antimicrobial peptides, is reported from the venom gland transcriptome of Cupiennius salei by 454- and Illumina 3000 sequencing. Four transcript families with complex precursor structures are responsible for the expression of 179 linear peptides. Within the transcript families, after an anionic propeptide, cationic linear peptides are separated by anionic linkers, which are transcript family specific. The C-terminus of the transcript families is characterized by a linear peptide or truncated linkers with unknown function. A new identified posttranslational processing mechanism explains the presence of the two-chain CsTx-16 family in the venom. The high diversity of linear peptides in the venom of a spider and this unique synthesis process is at least genus specific as verified with Cupiennius getazi.
2. Cupiennin 1d*: the cytolytic activity depends on the hydrophobic N-terminus and is modulated by the polar C-terminus
Lucia Kuhn-Nentwig, Margitta Dathe, Alfred Walz, Johann Schaller, Wolfgang Nentwig FEBS Lett. 2002 Sep 11;527(1-3):193-8. doi: 10.1016/s0014-5793(02)03219-2.
To investigate structural features modulating the biological activity of cupiennin 1 peptides from the spider Cupiennius salei, three truncated cupiennin 1d analogs were synthesized. The fact that their growth inhibiting effect on Gram-negative and Gram-positive bacteria, their lytic activity with human red blood cells and their insecticidal effect on Drosophila melanogaster correlates with structural properties shows that the hydrophobic N-terminal chain segment includes the major determinants of structure and activity. The polar C-terminus seems to modulate peptide accumulation at negatively charged cell surfaces via electrostatic interactions and has no important effect on the peptides' amphipathic secondary structure.
