Worms’ Antimicrobial Peptides

Abstract

Antimicrobial peptides (AMPs) are natural antibiotics produced by all living organisms. In metazoans, they act as host defense factors by eliminating microbial pathogens. But they also help to select the colonizing bacterial symbionts while coping with specific environmental challenges. Although many AMPs share common structural characteristics, for example having an overall size between 10–100 amino acids, a net positive charge, a γ-core motif, or a high content of cysteines, they greatly differ in coding sequences as a consequence of multiple parallel evolution in the face of pathogens. The majority of AMPs is specific of certain taxa or even typifying species. This is especially the case of annelids (ringed worms). Even in regions with extreme environmental conditions (polar, hydrothermal, abyssal, polluted, etc.), worms have colonized all habitats on Earth and dominated in biomass most of them while co-occurring with a large number and variety of bacteria. This review surveys the different structures and functions of AMPs that have been so far encountered in annelids and nematodes. It highlights the wide diversity of AMP primary structures and their originality that presumably mimics the highly diverse life styles and ecology of worms. From the unique system that represents marine annelids, we have studied the effect of abiotic pressures on the selection of AMPs and demonstrated the promising sources of antibiotics that they could constitute.

Effectiveness of Aqueous Extract of Marine Baitworm Marphysa moribidii Idris, Hutchings and Arshad, 2014 (Annelida, Polychaeta), on Acute Wound Healing Using Sprague Dawley Rats

“…The water seemed ineffective in extracting more antibacterial compounds from M. moribidii , where 0.4 g/ml had shown insufficient value to inhibit bacterial growth. Nevertheless, the solubility problem during the polychaete extraction might be overcome in the future by choosing other solvents such as methanol and ethanol [ 31 , 32 ]. These solvents probably have higher abilities to extract more bioactive compounds from the polychaete extract with antibacterial properties.…”

“…For instance, ethanol extract of other polychaete species, Halla parthenopeia , Hydroides elegans , and Perinereis cultifera showed positive antibacterial effect against P. aeruginosa , Bacillus cereus , and E. coli , respectively [ 32 , 33 ]. Arenicola marina , a coastal polychaete, was the first finding reported to produce arenicin-1, an antimicrobial peptide, which assembles on the negatively charged bacterial membrane and gives a lethal effect on the microbes [ 32 ]. Thus, the ability of aqueous M. moribidii extract to combat pathogenic bacteria is required to be confirmed through other studies.…”

Medicinal Perspective of Antibacterial Bioactive Agents in Earthworms (Clitellata, Annelida): A Comprehensive Review

“…antibiotics) that control bacterial growth and produced by living organisms ranged from ancient bacteria to modern mammals. In multi-cellular organisms, they perform essential function as defensive molecule by working in the front line of microbe s immunity such as fungi, bacteria, and protozoa 25,26) , that try to invade and proliferate in the living host 27) . These antibacterial peptides can be classified into five different biochemical groups on the basis of form and structure: (a) linear peptides without cysteine amino acid, often form amphipathic compounds, (b) linear peptides consist of increase proportion of various amino acids like proline, (c) peptides with loop form and containing one disulfide linkage, (d) peptides with β pleated sheets and having two or more disulfide bridge, (e) peptides formed from complex molecules with multiple known functions 28) .…”

Antimicrobial Peptides: Novel Source and Biological Function With a Special Focus on Entomopathogenic Nematode/Bacterium Symbiotic Complex

“…The AMP cecropins are found in the worm Ascaris suum (cecropin-P1, cecropin-P2, cecropin-P3, and cecropin-P4), a parasite inhabiting the intestine of pigs. These short AMPs, rich in serine residues, are stabilized by the disulfide bonds and contain potential antimicrobial activities against BPB (S. aureus, B. subtilis, Micrococcus luteus) and GNB (Pseudomonas aeruginosa, Salmonella typhimurium, Serratia marcescens, and E. coli) and are less effective against fungi (Saccharomyces cerevisiae, C. albicans) (Andrä et al, 2001;Andersson et al, 2003;Pillai et al, 2005;Bruno et al, 2019). Cecropin P1-like sequences were also identified in two other species, i.e., Ascaris lumbricoides and Toxocara canis (Pillai et al, 2005).…”