Phages are recognized as the most abundant and diverse entities on planet. Their diversity is determined predominantly by their dynamic adaptation capacities when confronted with different selective pressures in an endless cycle of coevolution a widespread group bacterial hosts. At end infection cycle, progeny virions rigid cell wall that hinders release into environment opportunity to start new cycle. Consequently, phages encode hydrolytic enzymes, called endolysins, digest peptidoglycan....

Resistance rates are increasing among several problematic Gram-negative pathogens, a fact that has encouraged the development of new antimicrobial agents. This paper characterizes Salmonella phage endolysin (Lys68) and demonstrates its potential effectiveness when combined with organic acids towards pathogens. Biochemical characterization reveals Lys68 is more active at pH 7.0, maintaining 76.7% activity stored 4°C for two months. Thermostability tests showed only completely inactivated upon...

The in vivo efficacy of many therapeutic peptides is hampered by their rapid proteolytic degradation. Cyclization these an excellent way to render them more resistant against breakdown. Here, we describe the enzymatic introduction a thioether ring angiotensin [Ang-(1-7)], heptapeptide that plays pivotal role renin-angiotensin system and possesses important activities. lactic acid bacterium <i>Lactococcus lactis</i>, equipped with plasmid-based nisin modification machinery, was used produce...

The present study demonstrates the antibacterial potential of a phage endolysin against Gram-negative pathogens, particularly multidrug resistant strains Acinetobacter baumannii. We have cloned, heterologously expressed and characterized novel (ABgp46) from vb_AbaP_CEB1 tested its activity several multidrug-resistant A. baumannii strains. LC-MS revealed that ABgp46 is an N-acetylmuramidase, also active over broad pH range (4.0-10.0) temperatures up to 50°C. Interestingly, has intrinsic...

Abstract Orally administered phages to control zoonotic pathogens face important challenges, mainly related the hostile conditions found in gastrointestinal tract (GIT). These include temperature, salinity and primarily pH, which is exceptionally low certain compartments. Phage survival under these can be jeopardized undermine treatment. Strategies like encapsulation have been attempted with relative success, but are typically complex require several optimization steps. Here we report a...

Lantibiotics are lanthionine-containing peptide antibiotics. Nisin, encoded by nisA, is a pentacyclic lantibiotic produced some Lactococcus lactis strains. Its thioether rings posttranslationally introduced membrane-bound enzyme complex. This complex composed of three enzymes: NisB, which dehydrates serines and threonines; NisC, couples these dehydrated residues to cysteines, thus forming rings; the transporter NisT. We followed activity various combinations nisin enzymes measuring export...

ABSTRACT Nisin A is a pentacyclic antibiotic peptide produced by various Lactococcus lactis strains. displays four different activities: (i) it autoinduces its own synthesis; (ii) inhibits the growth of target bacteria membrane pore formation; (iii) bacterial interfering with cell wall and, in addition, (iv) outgrowth spores. Here we investigate structural requirements and relevance N-terminal thioether rings nisin randomization ring B positions. The data demonstrate that: mutation results...

Post-translationally introduced dehydroamino acids often play an important role in the activity and receptor specificity of biologically active peptides. In addition, a acid can be coupled to cysteine yield cyclized peptide with increased biostability resistance against proteolytic degradation and/or modified specificity. The lantibiotic nisin is antimicrobial produced by Lactococcus lactis. Its post-translational enzymatic modification involves NisB-mediated dehydration serines threonines...

Nisin A is a pentacyclic peptide antibiotic produced by Lactococcus lactis. The leader of prenisin keeps nisin inactive and has role in inducing NisB- NisC-catalyzed modifications the propeptide NisT-mediated export. highly specific NisP cleaves off from fully modified exported prenisin. We present here detailed mutagenesis analysis peptide. For alternative cleavage, we successfully introduced putative autocleavage site sites for thrombin, enterokinase, Glu-C, factor Xa C-terminal part...

Milk processing lines offer a wide variety of microenvironments where diversity microorganisms can proliferate. We sampled crevices and junctions where, due to deficient reach by typical sanitizing procedures, bacteria survive establish biofilms. The sampling sites were the holding cell, cold storage tank, pasteurizer tank - transfer pump junction. culturable that isolated after sanitation procedure predominantly Pseudomonas spp., Serratia spp, Staphylococcus sciuri Stenotrophomonas...

Nisin is a pentacyclic peptide antibiotic active against Gram-positive bacteria. Its thioether rings are formed by two enzymatic steps: nisin dehydratase (NisB)-mediated dehydration of serines and threonines followed cyclase (NisC)-catalyzed enantioselective coupling cysteines to the dehydroresidues. Here, we report in vivo activity NisC cyclize wide array unrelated designed peptides that were fused leader peptide. To assess role NisC, fusions, secreted Lactococcus lactis cells containing...

OPINION article Front. Pharmacol., 07 September 2015Sec. Drugs Outcomes Research and Policies Volume 6 - 2015 | https://doi.org/10.3389/fphar.2015.00180

Curcuminoids are phenylpropanoids with high pharmaceutical potential. Herein, we report an engineered artificial pathway in Escherichia coli to produce natural curcuminoids through caffeic acid. Arabidopsis thaliana 4-coumaroyl-CoA ligase and Curcuma longa diketide-CoA synthase (DCS) curcumin (CURS1) were used 70 mg/L of was obtained from ferulic Bisdemethoxycurcumin demethoxycurcumin also produced, but lower concentrations, by feeding p-coumaric acid or a mixture acid, respectively....

Triple negative breast cancer (TNBC) is a particular immunopathological subtype of that lacks expression estrogen and progesterone receptors (ER/PR) amplification the human epidermal growth factor receptor 2 (HER2) gene. Characterized by aggressive metastatic phenotypes high rates relapse, TNBC only subgroup still lacking effective therapeutic options, thus presenting worst prognosis. The development targeted therapies, as well early diagnosis methods, vital to ensure an adequate timely...

ABSTRACT Nisin is a pentacyclic peptide antibiotic produced by some Lactococcus lactis strains. contains dehydroresidues and thioether rings that are posttranslationally introduced membrane-associated enzyme complex, composed of serine threonine dehydratase NisB the cyclase NisC. In addition, transporter NisT necessary for export modified peptide. We studied potential L. expressing to produce peptides whose serines threonines dehydrated. containing nisBT genes plasmid coding specific leader...

Endolysins, which are peptidoglycan-degrading enzymes expressed during the terminal stage of reproduction cycle bacteriophages, have great potential to control Gram-positive pathogens. This work describes characterization a novel endolysin (PlyPl23) encoded on genome Paenibacillus larvae phage phiIBB_Pl23 with high American foulbrood. bacterial disease, caused by P. larvae, is widespread in North America and Europe causes important economic losses apiculture. The restriction antibiotic...

The use of bacteriophages to select novel ligands has been widely explored for cancer therapy. Their application is most warranted in subtypes lacking knowledge on how target the cells question, such as triple negative breast cancer, eventually leading development alternative nanomedicines therapeutics. Therefore, following study aimed and characterize peptides a murine mammary carcinoma cell line- 4T1. Using phage display, 7 12 amino acid random peptide libraries were screened against 4T1...

The ability of the hyperthermophilic bacterium Thermotoga maritima to grow on pectin as a sole carbon source coincides with secretion pectate lyase A (PelA) in extracellular medium. pel gene T. was functionally expressed Escherichia coli first heterologously produced thermophilic pectinase, and purified homogeneity. Gel filtration indicated that native form PelA is tetrameric. Highest activity (422 units/mg, K(m) 0.06 mM) demonstrated polygalacturonic acid (PGA), whereas pectins an...