A novel type I cystatin of parasite origin with atypical legumain-binding domain.
Jana IlgováLucie JedličkováHana DvořákováMichal BenovicsLibor MikešLubomír JandaJiří VorelPavel RoudnickýDavid PotěšilZbyněk ZdráhalMilan GelnarMartin KašnýPublished in: Scientific reports (2017)
Parasite inhibitors of cysteine peptidases are known to influence a vast range of processes linked to a degradation of either the parasites' own proteins or proteins native to their hosts. We characterise a novel type I cystatin (stefin) found in a sanguinivorous fish parasite Eudiplozoon nipponicum (Platyhelminthes: Monogenea). We have identified a transcript of its coding gene in the transcriptome of adult worms. Its amino acid sequence is similar to other stefins except for containing a legumain-binding domain, which is in this type of cystatins rather unusual. As expected, the recombinant form of E. nipponicum stefin (rEnStef) produced in Escherichia coli inhibits clan CA peptidases - cathepsins L and B of the worm - via the standard papain-binding domain. It also blocks haemoglobinolysis by cysteine peptidases in the worm's excretory-secretory products and soluble extracts. Furthermore, we had confirmed its ability to inhibit clan CD asparaginyl endopeptidase (legumain). The presence of a native EnStef in the excretory-secretory products of adult worms, detected by mass spectrometry, suggests that this protein has an important biological function at the host-parasite interface. We discuss the inhibitor's possible role in the regulation of blood digestion, modulation of antigen presentation, and in the regeneration of host tissues.
Keyphrases
- plasmodium falciparum
- amino acid
- toxoplasma gondii
- trypanosoma cruzi
- escherichia coli
- mass spectrometry
- binding protein
- life cycle
- stem cells
- gene expression
- dna binding
- genome wide
- rna seq
- fluorescent probe
- liquid chromatography
- living cells
- copy number
- staphylococcus aureus
- high resolution
- case report
- childhood cancer
- young adults
- cell free
- protein protein
- biofilm formation
- genome wide identification
- small molecule
- candida albicans