Metalloproteases (Astacins) |
Feitosa et al. [3232. Feitosa L, Gremski W, Veiga SS, Elias MCQB, Graner E, Mangili OC, et al. Detection and characterization of metalloproteinases with gelatinolytic, fibronectinolytic and fibrinogenolytic activities in Brown spider (Loxosceles intermedia) venom. Toxicon. 1998 Jul;36(7):1039-51.], 1998 |
L. intermedia venom was able to degrade fibronectin and fibrinogen, but not laminin or types I and IV collagens. This activity was blocked by EDTA and 1,10-phenantroline. Zymogram analyzes of venom detected a 35 kDa enzyme with gelatinolytic activity and a fibronectinolytic and fibrinogenolytic band at 28 kDa. |
Da Silveira et al. [4040. da Silveira RB, Wille ACM, Chaim OM, Appel MH, Silva DT, Franco CRC, et al. Identification, cloning, expression and functional characterization of an astacin-like metalloprotease toxin from Loxosceles intermedia (brown spider) venom. Biochem J. 2007 Sep 1;406(2):355-63.], 2007 |
A 30 kDa metalloprotease was cloned and produced a recombinant protein in a prokaryotic expression system. It was named LALP1, from Loxosceles astacin-like protease, because it was structurally and functionally related to the astacin family of metalloproteases. LALP1 induced de-adhesion of endothelial cell cultures and degraded fibronectin and fibrinogen. |
Trevisan-Silva et al. [122122. Trevisan-Silva D, Gremski LH, Chaim OM, da Silveira RB, Meissner GO, Mangili OC, et al. Astacin-like metalloproteases are a gene family of toxins present in the venom of different species of the brown spider (genus Loxosceles). Biochimie. 2010 Jan;92(1):21-32.], 2010 |
Two novel cDNAs encoding astacins were cloned from L. intermedia venom glands (LALP2 and LALP3). The venoms of L. intermedia, L. laeta and L. gaucho showed immunologically-related toxins with LALP1 and toxins with gelatinolytic activity with the same electrophoretic mobilities. The screening of mRNAs from L. laeta and L. gaucho venom glands revealed members of the astacin family (LALP4 and LALP5, respectively). |
Trevisan-Silva et al. [4444. Trevisan-Silva D, Gremski LH, Chaim OM, Senff-Ribeiro A, Veiga SS. Loxosceles Astacin-Like Proteases (LALPs). Handb Proteolytic Enzym. 2013 Dec:1081-6. ], 2013 |
Based on the analysis of subproteomes of LALPs from L. intermedia, L. laeta and L. gaucho, authors showed that LALPs comprise a large family of toxins in Loxosceles venom, and that each venom has distinct proteolytic activities. |
Morgon et al. [4646. Morgon AM, Belisario-Ferrari MR, Trevisan-Silva D, Meissner GO, Vuitika L, Marin B, et al. Expression and immunological cross-reactivity of LALP3, a novel astacin-like metalloprotease from brown spider (Loxosceles intermedia) venom. Biochimie. 2016 Sep-Oct;128-129:8-19.], 2017 |
LALP3 was expressed using a SUMO tag in Escherichia coli Shuffle T7 Express LysY cells. Immunoassays showed that LALP1 and LALP3 share linear epitopes and LALP3 shares conformational epitopes with native venom astacins. Molecular modeling of LALP3 revealed the zinc binding and Met-turn motifs forming the active site. |
Medina-Santos et al. [4141. Calabria PAL, Shimokava-Falcao LHAL, Colombini M, Moura-da-Silva AM, Barbaro KC, Faquim-Mauro EL, et al. Design and production of a recombinant hybrid toxin to raise protective antibodies against Loxosceles spider venom. Toxins (Basel). 2019 Feb 12;11(2):1-21.], 2019 |
L. laeta venom gland transcripts were analyzed with a focus on LALPs and nine possible LALPs isoforms from Peruvian L. laeta venom were identified and validated by in silico and in vitro experiments. |
Serine proteases |
Veiga et al. [5151. Veiga SS, Da Silveira RB, Dreyfuss JL, Haoach J, Pereira AM, Mangili OC, et al. Identification of high molecular weight serine-proteases in Loxosceles intermedia (brown spider) venom. Toxicon. 2000 Jun;38(6):825-39.], 2000 |
Serine protease activity was detected in the venom of L. intermedia after treatment with trypsin. These gelatinolytic molecules presented electrophoretic mobility of 85 and 95 kDa in a zymogram analysis. |
Hyaluronidases |
Da Silveira et al. [6666. da Silveira RB, Chaim OM, Mangili OC, Gremski W, Dietrich CP, Nader HB, et al. Hyaluronidases in Loxosceles intermedia (Brown spider) venom are endo-β-N-acetyl-d-hexosaminidases hydrolases. Toxicon. 2007 May;49(6):758-68.], 2006 |
L. intermedia venom hyaluronidases were characterized as endo-β-N-acetyl-D-hexosaminidases that hydrolyze hyaluronic acid (HA) and chondroitin sulfate (CS). Lytic activities upon these GAGs were observed by zymogram analyzes at 41 and 43 kDa. |
Ferrer et al. [6868. Ferrer VP, de Mari TL, Gremski LH, Trevisan Silva D, da Silveira RB, Gremski W, et al. A Novel Hyaluronidase from Brown Spider (Loxosceles intermedia) Venom (Dietrich’s Hyaluronidase): From Cloning to Functional Characterization. PLoS Negl Trop Dis. 2013 May;7(5):1-12.], 2013 |
A recombinant hyaluronidase (Dietrich’s hyaluronidase) from L. intermedia venom was expressed and refolded. It was able to degrade HA and CS, cross-reacted with native venom toxins and increased the dermonecrotic effect of a Loxosceles PLD, confirming its activity as a spreading factor. |
De-Bona et al. [7171. De-Bona E, Chaves-Moreira D, Batista TBD, Justa HC da, Rossi GR, Antunes BC, et al. Production of a novel recombinant brown spider hyaluronidase in baculovirus-infected insect cells. Enzyme Microb Technol. 2021 May;109759(146).], 2021 |
A novel hyaluronidase of L. intermedia venom was produced in a baculovirus-insect cell expression system as a fully active enzyme with post-translationally modifications (i.e., N-linked carbohydrates). LiHyal2, as it was named, potentialized dermonecrosis, edema and vascular permeability induced by a Loxosceles PLD. |
Allergens |
Justa et al. [1919. Justa HC, Matsubara FH, de-Bona E, Schemczssen-Graeff Z, Polli NLC, de Mari TL, et al. LALLT (Loxosceles Allergen-Like Toxin) from the venom of Loxosceles intermedia: Recombinant expression in insect cells and characterization as a molecule with allergenic properties. Int J Biol Macromol. 2020 Dec 1;164:3984-99.], 2020 |
A novel allergen toxin, named LALLT, was produced in a eukaryotic expression system and triggered paw edema and increased vascular permeability in mice. LALLT also induced erythema, edema and leukocyte infiltration in rabbit skin. The degranulation of mastocytes by LALLT was observed in vivo and in vitro. RNA screening indicated the presence of allergen toxins in the venom of other Loxosceles spiders. |
Translationally controlled tumor protein (TCTP) |
Sade et al. [8787. Sade YB, Bóia-Ferreira M, Gremski LH, Da Silveira RB, Gremski W, Senff-Ribeiro A, et al. Molecular cloning, heterologous expression and functional characterization of a novel translationally-controlled tumor protein (TCTP) family member from Loxosceles intermedia (brown spider) venom. Int J Biochem Cell Biol. 2012 Jan;44(1):170-7.], 2012 |
A novel member of the TCTP family from L. intermedia venom gland was heterologously expressed and purified. LiTCTP caused edema and enhanced vascular permeability. |
Boia-Ferreira et al. [8888. Boia-Ferreira M, Moreno KG, Basílio ABC, da Silva LP, Vuitika L, Soley B, et al. TCTP from Loxosceles Intermedia (Brown Spider) Venom Contributes to the Allergic and Inflammatory Response of Cutaneous Loxoscelism. Cells. 2019 Nov 22;8(12):1489.], 2019 |
LiTCTP was characterized as an essential synergistic factor for the dermonecrotic toxin action, increasing the inflammatory response, capillary permeability, edema and contributing to the exacerbated inflammatory response. |
ICK peptides |
De Castro et al. [110110. De Castro CS, Silvestre FG, Araújo SC, Yazbeck GDM, Mangili OC, Cruz I, et al. Identification and molecular cloning of insecticidal toxins from the venom of the brown spider Loxosceles intermedia. Toxicon. 2004 Sep 1;44(3):273-80.], 2004 |
Native peptides with insecticidal activity (LiTx1, LiTx2 and LiTx3) were purified from L. intermedia venom by using chromatographic approaches. |
Matsubara et al. [117117. Matsubara FH, Gremski LH, Meissner GO, Constantino Lopes ES, Gremski W, Senff-Ribeiro A, et al. A novel ICK peptide from the Loxosceles intermedia (brown spider) venom gland: Cloning, heterologous expression and immunological cross-reactivity approaches. Toxicon. 2013 Sep;71:147-58.], 2013 |
U2-SCRTX-Li1b, an ICK peptide from L. intermedia, was heterologously expressed in bacteria - first ICK peptide from Loxosceles spiders to be produced in its recombinant form. Immunoblotting assays pointed out that ICK peptides constitute a family of toxins conserved in the genus. |
Meissner et al. [119119. Meissner GO, de Resende Lara PT, Scott LPB, Braz ASK, Chaves-Moreira D, Matsubara FH, et al. Molecular cloning and in silico characterization of knottin peptide, U2-SCRTX-Lit2, from brown spider (Loxosceles intermedia) venom glands. J Mol Model. 2016 Sep;22(9):196.], 2016 |
U2-SCRTX-Lit2, another ICK peptide of L. intermedia, was cloned. Molecular dynamics analysis revealed that U2-SCRTX-Lit2 possibly acts as a steric blocker, hiding the gate access of Na+-voltage-gated channels. |
Matsubara et al. [111111. Matsubara FH, Meissner GO, Herzig V, Justa HC, Dias BCL, Trevisan-Silva D, et al. Insecticidal activity of a recombinant knottin peptide from Loxosceles intermedia venom and recognition of these peptides as a conserved family in the genus. Insect Mol Biol. 2017 Feb;26(1):25-34.], 2017 |
U2-SCRTX-Li1b was heterologously expressed in the periplasm of bacteria. U2-SCRTX-Li1b caused long-lasting paralysis in sheep blowflies, which was irreversible even after 72 h - first recombinant ICK peptide from Loxosceles spiders to have its activity determined. ICK peptides were identified from the RNA extracted from the venom-producing glands of L. gaucho and L. laeta - first study to identify ICK peptides in species other than L. intermedia. |