Effect and Mechanisms of Antibacterial Peptide Fraction from Mucus of C. aspersum against Escherichia coli NBIMCC 8785

Abstract

Peptides isolated from the mucus of Cornu aspersum could be prototypes for antibiotics against pathogenic bacteria. Information regarding the mechanisms, effective concentration, and methods of application is an important tool for therapeutic, financial, and ecological regulation and a holistic approach to medical treatment. A peptide fraction with MW < 10 kDa was analyzed by MALDI-TOF-TOF using Autoflex™ III. The strain Escherichia coli NBIMCC 8785 (18 h and 48 h culture) was used. The changes in bacterial structure and metabolic activity were investigated by SEM, fluorescent, and digital image analysis. This peptide fraction had high inhibitory effects in surface and deep inoculations of E. coli of 1990.00 and 136.13 mm2/mgPr/µMol, respectively, in the samples. Thus, it would be effective in the treatment of infections involving bacterial biofilms and homogenous cells. Various deformations of the bacteria and inhibition of its metabolism were discovered and illustrated. The data on the mechanisms of impact of the peptides permitted the formulation of an algorithm for the treatment of infections depending on the phase of their development. The decrease in the therapeutic concentrations will be more sparing to the environment and will lead to a decrease in the cost of the treatment.

Snail Mucus Protective Effect on Ethanol-Induced Gastric Ulcers in Mice

“…In the region above 100 kDa, proteins might correspond to glycoproteins and mucins. More details on the C. aspersum mucus composition based on our earlier studies [ 15 , 18 , 19 , 25 , 26 , 27 ] are presented in Table 1 . A number of new peptides have been isolated from the mucus, and their amino acid sequences were determined by de novo sequencing and by MALDI-TOF-MS/MS analyses; some of them are presented in Table 1 .…”

“…Trapella et al [ 16 ] also suggested that snail mucus’s potential as a therapeutic agent in wound repair was attributable to the synergistic activity of several molecules. In mucus, such as we have used in the present paper, the primary structures of novel antimicrobial peptides with molecular weights mainly between 1–3 kDa were identified by tandem mass spectrometry ( Table 1 ), and their antibacterial activity was demonstrated [ 18 , 26 ]. The C. aspersum mucus contains both cationic and anionic and neutral peptides, but cationic are dominant.…”

“…The C. aspersum mucus contains both cationic and anionic and neutral peptides, but cationic are dominant. That is considered a prerequisite for observed mucus antimicrobial activity—destruction of biological membranes and/or direct cell lysis [ 18 , 26 ]. The antimicrobial activity was predicted based on the identified primary structures using iAMPpred software (online prediction server available at , accessed on 10 June 2022).…”

“…It is known that cationic antimicrobial peptides kill microbes via mechanisms that predominantly involve interactions between the peptide’s positively charged residues and anionic components of the target cell’s membranes. Moreover, some of the positively charged peptides may penetrate into the cell to bind intracellular molecules that are crucial to the life of the cell [ 26 ]. Recently, different peptide and protein fractions from the C. aspersum mucus demonstrated antimicrobial and antioxidant activity as well as regenerative properties [ 18 , 19 , 36 ].…”

“… * Peptides’ physicochemical characteristics (isoelectric points (pI), grand average of hydropathicity (GRAVY), and net charge) were determined using the ExPASy ProtParam tool [ 24 ]. a Vassilev et al, 2020 [ 19 ]; b Kostadinova et al, 2018 [ 15 ]; c Beluhova et al, 2022 [ 25 ]; d Dolashki et al, 2020 [ 18 ]; e Topalova et al, 2022 [ 26 ]; f Velkova et al, 2018 [ 27 ]. …”