Disulphide bonds of the peptide protegrin-1 are not essential for antimicrobial activity and haemolytic activity

2010 ◽  
Vol 36 (6) ◽  
pp. 579-580 ◽  
Author(s):  
Raymond Murray Dawson ◽  
Chun-Qiang Liu
Keyword(s):  
Antimicrobial Activity ◽  
Haemolytic Activity ◽  
Disulphide Bonds

scholarly journals In Vitro Assessment for Antimicrobial Activity of Lactobacillus Helveticus and its Natural Glycopeptides Against Mastitis Causing Pathogens in Dairy Cat

2015 ◽  
Vol 9 (1) ◽  
pp. 61-66 ◽  
Author(s):  
Gundega Gulbe ◽  
Anda Valdovska ◽  
Vaira Saulite ◽  
Jevgenijs Jermolajevs
Keyword(s):  
Antimicrobial Activity ◽  
Lactic Acid ◽  
Pathogenic Bacteria ◽  
Antimicrobial Effect ◽  
Lactobacillus Helveticus ◽  
Haemolytic Activity ◽  
Pathogenic Microorganisms ◽  
Bacterial Strains ◽  
Coagulase Negative Staphylococci

Probiotic lactic acid bacteria have a great potential to control bovine mastitis as well as they are favourable choice to treat many infectious diseases of human. These bacteria are well known as having many properties which make them beneficial to control pathogenic microorganisms. These include, the ability to adhere to cell, the reduction of pathogenic bacteria adherents, the co–aggregation, the production of organic acids, hydrogen peroxide, bacteriocin and etc., to be safe and non–pathogenic, which antagonize pathogenic microorganisms. However, each strain must be well identified and characterized in vitro before using for disease treatment. The aim of the present study was to screen three kind of test suspensions: TS1, TS2 and TS3, which contains probiotic lactic acid bacterium Lactobacillus helveticus or its natural glycopeptides, and other natural immunomodulators, in order to investigate which content were the most effective in inhibiting several mastitis causing bacteria in dairy cattle: coagulase–positive Staphylococcus aureus, coagulase–negative staphylococci S. haemolyticus, S. saprophyticus, S. simulans, S. vitulinus, and Gram–negative bacteria Citrobacter freundii and Serratia liquefaciens. Test suspensions TS1, TS2 and TS3 were adjusted by pH 6.3, then tested in vitro by well diffusion assay to determine their antimicrobial effect against bacteria. Furthermore haemolytic activity of applied test suspensions were determined. In results TS1 (9-13 mm) and TS2 (10-15 mm) showed the inhibition effect on four of eight tested bacterial strains, whereas TS3 did not displayed any antimicrobial effect. TS2 have a greatest antimicrobial activity as they resulted in the largest inhibition zones.

scholarly journals Purification and biological activity of natural variants synthesized by tridecaptin M gene cluster and in vitro drug-kinetics of this antibiotic class

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Manoj Jangra ◽  
Manpreet Kaur ◽  
Mansi Podia ◽  
Rushikesh Tambat ◽  
Vidhu Singh ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Gene Cluster ◽  
Resistant Bacteria ◽  
Haemolytic Activity ◽  
M Gene ◽  
High Density Culture ◽  
Antibiotic Effect ◽  
Natural Variants ◽  
Drug Kinetics

AbstractThe flexibility of the adenylation domains of non-ribosomal peptide synthetases (NRPSs) to different substrates creates a diversity of structurally similar peptides. In the present study, we investigated the antimicrobial activity of different natural variants synthesized by tridecaptin M gene cluster and performed the in vitro drug kinetics on this class. The natural variants were isolated and characterized using MALDI-MS and tandem mass spectrometry. All the peptides were studied for their antimicrobial activity in different pathogens, including colistin-resistant bacteria, and for haemolytic activity. Furthermore, in vitro drug kinetics was performed with tridecaptin M (or M1, the major product of the gene cluster). The natural variants displayed a varying degree of bioactivity with M11 showing the most potent antibacterial activity (MIC, 1–8 µg/ml), even against A. baumannii and P. aeruginosa strains. The in vitro kinetic studies revealed that tridecaptin M at a concentration of 16 µg/ml eradicated the bacteria completely in high-density culture. The compound demonstrated desirable post-antibiotic effect after two-hour exposure at MIC concentration. We also observed the reversal of resistance to this class of antibiotics in the presence of carbonyl cyanide m-chlorophenyl hydrazine (CCCP). Altogether, the study demonstrated that tridecaptins are an excellent drug candidate against drug-resistant Gram-negative bacteria. Future studies are required to design a superior tridecaptin by investigating the interactions of different natural variants with the target.

scholarly journals Inhibition of the reconstitution of the haemolytic activity of the first component of human complement by a pepsin-derived fragment of subcomponent C1q

1977 ◽  
Vol 161 (2) ◽  
pp. 239-245 ◽  
Author(s):  
K B M Reid ◽  
R B Sim ◽  
A P Faiers
Keyword(s):  
Type Ii Collagen ◽  
Inhibitory Effect ◽  
The Other ◽  
Haemolytic Activity ◽  
Type Ii ◽  
Rat Skin ◽  
Pepsin Digestion ◽  
Disulphide Bonds ◽  
Skin Collagen ◽  
Intact Molecule

1. A fragment of subcomponent C1q, which contained all the collagen-like features present in the intact molecule, was isolated by pepsin digestion as described by Reid [Biochem. J. (1976) 155, 5-17]. 2. The pepsin-derived fragment of subcomponent C1q did not bind to antibody-coated erythrocytes under conditions where complete binding of sub-component C1q took place. 3. The peptic fragment blocked the reconstitution of C1 haemolytic activity by competing with intact subcomponent C1q in the utilization of a mixture of the other two subcomponents, C1r and C1s. 4. Reduction and alkylation of the interchain disulphide bonds in the pepsin fragment did not markedly affect its inhibitory effect, whereas heating at 56 degrees C for 30min completely abolished the effect. 5. Lathyritic rat skin collagen and CNBr-derived peptides of pig type II collagen showed no ability to mimic the inhibitory effect of the pepsin fragment when tested over the same concentration range as used for the peptic fragment. 6. The peptic fragment was unable to block efficiently the reconstitution of C1 haemolytic activity unless it was added to the mixture of subcomponents C1r and C1s before the attempt to reconstitute C1 haemolytic activity, in solution, or on the surface of antibody-coated erythrocytes. 7. Evidence was obtained that suggested that subcomponent C1q bound the subcomponent C1r-C1s complex more efficiently when the subcomponent C1q was bound to antibody than when it was free in solution.

scholarly journals Lactiplantibacillus plantarum strains isolated from spontaneously fermented cocoa exhibit potential probiotic properties against Gardnerella vaginalis and Neisseria gonorrhoeae

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Nathan das Neves Selis ◽  
Hellen Braga Martins de Oliveira ◽  
Hiago Ferreira Leão ◽  
Yan Bento dos Anjos ◽  
Beatriz Almeida Sampaio ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Neisseria Gonorrhoeae ◽  
Clinical Importance ◽  
Gardnerella Vaginalis ◽  
Haemolytic Activity ◽  
Probiotic Properties ◽  
Vaginal Infections ◽  
Probiotic Potential

Abstract Background Probiotics are important tools in therapies against vaginal infections and can assist traditional antibiotic therapies in restoring healthy microbiota. Recent research has shown that microorganisms belonging to the genus Lactobacillus have probiotic potential. Thus, this study evaluated the potential in vitro probiotic properties of three strains of Lactiplantibacillus plantarum, isolated during the fermentation of high-quality cocoa, against Gardnerella vaginalis and Neisseria gonorrhoeae. Strains were evaluated for their physiological, safety, and antimicrobial characteristics. Results The hydrophobicity of L. plantarum strains varied from 26.67 to 91.67%, and their autoaggregation varied from 18.10 to 30.64%. The co-aggregation of L. plantarum strains with G. vaginalis ranged from 14.73 to 16.31%, and from 29.14 to 45.76% with N. gonorrhoeae. All L. plantarum strains could moderately or strongly produce biofilms. L. plantarum strains did not show haemolytic activity and were generally sensitive to the tested antimicrobials. All lactobacillus strains were tolerant to heat and pH resistance tests. All three strains of L. plantarum showed antimicrobial activity against the tested pathogens. The coincubation of L. plantarum strains with pathogens showed that the culture pH remained below 4.5 after 24 h. All cell-free culture supernatants (CFCS) demonstrated activity against the two pathogens tested, and all L. plantarum strains produced hydrogen peroxide. CFCS characterisation in conjunction with gas chromatography revealed that organic acids, especially lactic acid, were responsible for the antimicrobial activity against the pathogens evaluated. Conclusion The three strains of L. plantarum presented significant probiotic characteristics against the two pathogens of clinical importance. In vitro screening identified strong probiotic candidates for in vivo studies for the treatment of vaginal infections.

Reduction of disulphide bonds unmasks potent antimicrobial activity of human β-defensin 1

Nature ◽  
2011 ◽  
Vol 469 (7330) ◽  
pp. 419-423 ◽  
Author(s):  
Bjoern O. Schroeder ◽  
Zhihong Wu ◽  
Sabine Nuding ◽  
Sandra Groscurth ◽  
Moritz Marcinowski ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Disulphide Bonds

scholarly journals Antimicrobial activity and mechanism of action of a novel peptide present in the ecdysis process of centipede Scolopendra subspinipes subspinipes

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Elisa Chaparro-Aguirre ◽  
Paula J. Segura-Ramírez ◽  
Flavio L. Alves ◽  
Karin A. Riske ◽  
Antonio Miranda ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Mechanism Of Action ◽  
Mass Spectrometry Analysis ◽  
Haemolytic Activity ◽  
Promising Candidate ◽  
Spectrometry Analysis ◽  
Cellular Events ◽  
Cuticular Proteins ◽  
High Concentrations ◽  
Conventional Antibiotics

Abstract One of the most important cellular events in arthropods is the moulting of the cuticle (ecdysis). This process allows them to grow until they reach sexual maturity. Nevertheless, during this stage, the animals are highly exposed to pathogens. Consequently, it can be assumed that arthropods counter with an efficient anti-infective strategy that facilitates their survival during ecdysis. Herein, we characterized a novel antimicrobial peptide called Pinipesin, present in the exuviae extract of the centipede Scolopendra subspinipes subspinipes. The antimicrobial activity of Pinipesin was tested. The haemolytic activity of the peptide was evaluated and its possible mechanism of action was investigated. Identification was carried out by mass spectrometry analysis. Pinipesin displayed potent antimicrobial effects against different microorganisms and showed low haemolytic effects against human erythrocytes at high concentrations. It has a monoisotopic mass of 1213.57 Da, its sequence exhibited high similarity with some cuticular proteins, and it might act intracellularly by interfering with protein synthesis. Our data suggest that Pinipesin might be part of a prophylactic immune response during the ecdysis process of centipedes. Therefore, it is a promising candidate for the development of non-conventional antibiotics that could help fight infectious diseases and represents an exciting discovery for this taxon.

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