Identification and functional characterization of the astacidin family of proline-rich host defence peptides (PcAst) from the red swamp crayfish (Procambarus clarkii, Girard 1852)

A Crustin from Hydrothermal Vent Shrimp: Antimicrobial Activity and Mechanism

“…The MIC and MBC were determined with the microdilution broth method [50]. In short, bacteria were cultured in MHB to an OD600 of 0.5-0.6 and diluted to 10 4 CFU/mL.…”

“…For microscopy with SEM (S-3400N, Hitachi, Tokyo, Japan), B. cereus MB1 and M. luteus were cultured in LB medium to logarithmic phase, and the cells were washed and resuspended in PBS to 1 × 10 6 CFU/mL. The cells were pretreated with 1 × MBC rCrus1 or PBS at 37 • C for 2 h. After treatment, the cells were fixed with 5% glutaraldehyde in PBS (pH 7.4) for 2 h and dehydrated in a series of increased concentration of ethanol (30,50,70,80, 90 and 100%) for 10 min at 4 • C. The cells were treated with isoamyl acetate for 10 min, critical point-dried (Hitachi-HCP, Hitachi, Japan), sputter-coated with platinum (MC1000, Hitachi, Japan) and examined with a SEM. For microscopy with TEM (HT7700, Hitachi, Tokyo, Japan), B. cereus and M. luteus were pretreated with rCrus1 or PBS as above.…”

A Comprehensive Review on Crustaceans’ Immune System With a Focus on Freshwater Crayfish in Relation to Crayfish Plague Disease

“…Fortunately, the TLRs are one of the well-conserved families of PRRs that perform a recognition role of diverse classes of pathogens including fungi, bacteria, and viruses. Several Toll receptors and related proteins have been identified in different freshwater crayfish, for example, Toll receptor 3 from A. astacus (120), PcToll1, 2, 3, 4, 5, and 6 from Procambarus clarkii (121)(122)(123)(124)(125)(126)(127). Crayfish PRRs represent lectins as an important class of molecules with a role of non-selfrecognition, however, lectins are proteins that bind to sugar using a characteristics carbohydrate recognition domain (CRD).…”

“…AMPs are widely distributed small cationic polypeptides that exert an anti-pathogenic effect on a broad spectrum of pathogens. Crustacean AMPs can generally be classified into four groups according to their amino acid compositions and structural properties ( 106 , 127 ) ( 1 ): single-domain amphipathic linear α-helical structure AMPs, including astacidins which are proline-rich peptides like astacidin 2 from P. leniusculus ( 137 ), and Pc-astacidin from P. clarkii ( 127 ) ( 2 ); single-domain peptides enriched with cysteine residues that are able to form at least one disulfide bridge between the B-sheets ( 3 ); AMPs with multi-domain linear α-helical peptides enriched with certain amino acids, generally proline and/or glycine residues, including crustins, characterized by their acidic protein (WAP) domain at C-terminus, such as Pl-crustin 1 & 2 in P. leniusculus , and Pc-crustin 4 in P. clarkii ( 138 , 139 ), and procambarins, the glycine-rich peptide described in P. clarkia ( 140 ); and ( 4 ) unconventional AMPs including proteins/protein-fragments with antimicrobial functions like H2A histones and anti-lipopolysaccharide factors (ALFs) (reviewed in 121, 126). Lastly, at least two types of invertebrate (i-types) lysozymes, Pclysi 1 and 2, have been identified in P. clarkii ( 141 ).…”

Characteristics of Two Crustins from Alvinocaris longirostris in Hydrothermal Vents

“…Antimicrobial activities were examined against seven Gram-positive and six Gram-negative bacteria. The MIC was determined by a liquid growth inhibition assay [34]. The purified proteins were consecutively diluted with sterile water in five multiples; next, 0.2% BSA was used as the negative control.…”