Ctenidins: antimicrobial glycine-rich peptides from the hemocytes of the spider Cupiennius salei

Abstract

Three novel glycine-rich peptides, named ctenidin 1-3, with activity against the Gram-negative bacterium E. coli, were isolated and characterized from hemocytes of the spider Cupiennius salei. Ctenidins have a high glycine content (>70%), similarly to other glycine-rich peptides, the acanthoscurrins, from another spider, Acanthoscurria gomesiana. A combination of mass spectrometry, Edman degradation, and cDNA cloning revealed the presence of three isoforms of ctenidin, at least two of them originating from simple, intronless genes. The full-length sequences of the ctenidins consist of a 19 amino acid residues signal peptide followed by the mature peptides of 109, 119, or 120 amino acid residues. The mature peptides are post-translationally modified by the cleavage of one or two C-terminal cationic amino acid residue(s) and amidation of the newly created mature C-terminus. Tissue expression analysis revealed that ctenidins are constitutively expressed in hemocytes and to a small extent also in the subesophageal nerve mass.

Innate Immune Responses of a Scleractinian Coral to Vibriosis

“…Despite this difference, damicornin shares several features in common with invertebrate defensins: (i) it is particularly active against Grampositive bacteria and filamentous fungi but has limited activity against Gram-negative bacteria; (ii) it is characterized by a lack of hemolytic activity (48); and (iii) in terms of structural features, it can also have C-terminal amidation (50,51). The latter is common among cationic AMPs; it makes them more resistant to proteolysis and increases their net positive charge (49,(52)(53)(54)(55)(56).…”

Purification, cDNA structure and biological significance of a single insulin-like growth factor-binding domain protein (SIBD-1) identified in the hemocytes of the spider Cupiennius salei

“…Spider breeding and hemocyte isolation were carried out as previously reported (Baumann et al, 2010a). Hemocytes were resuspended in double distilled water (ddH 2 O) containing 0.1% trifluoroacetic acid (TFA) and homogenized by ultrasonication (Sonoplus, Bandelin, Switzerland) twice for 1 min at 30% power, pulse level 5, on ice.…”

“…Our investigations into the immune system of non-infected araneomorph spiders (C. salei, Ctenidae) resulted in the identification of two families of antimicrobial peptides constitutively stored in hemocytes. The first family of these peptides is composed of Gly-rich ctenidins 1e3, which seem to be expressed mainly in hemocytes (Baumann et al, 2010a). From the second family, a defensin was identified on cDNA level, which is expressed in hemocytes, ovaries, subesophageal nerve mass, hepatopancreas, and muscle (Baumann et al, 2010b).…”

“…A leading role in this defense system is played largely by circulating hemocytes, which are produced as prohemocytes in a special inner layer of the heart wall of spiders (Seitz, 1972a). In Cupiennius salei, hemocytes are not only used in fighting invaders and healing wounds but also in molting and yolk integration of oocytes (Baumann et al, 2010a(Baumann et al, , 2010bSeitz, 1971Seitz, , 1972bSeitz, , 1976.…”

Peptídeos bioativos do plasma de <i>Acanthoscurria rondoniae</i>.

“…Recentemente, nos hemócitos da aranha Cupienius salei foi encontrado um peptideo antimicrobiano rico em glicina, "Ctenidin" muito semelhante à Acanthoscurrina (Baumann et al,2010). Também foi encontrado nos hemócitos da aranha caranguejeira A. gomesina uma molécula de baixo peso (417 Da), a migalina, uma acil poliamina com atividade contra bactérias Gram negativas e cuja atividade e inibida em presença de catalase, indicando um possível modo de ação através da produção de H 2 O 2 (peróxido de hidrogênio) (Silva Jr. et al,2000;Pereira et al,2007).…”