Design and pharmacodynamics of recombinant NZ2114 histidine mutants with improved activity against methicillin-resistant Staphylococcus aureus

Abstract

NZ2114 is a promising candidate for therapeutic application owing to its potent activity to Staphylococcus aureus. Our objective was to identify NZ2114 derivatives with improved activity through substitution of His16 and His18 with residues Arginine and Lysine. Eight mutants were designed and expressed in Pichia pastoris X-33 via pPICZαA. Five of them exhibited strong antimicrobial activity against S. aureus at low minimal inhibitory concentrations (MICs) of 0.057–0.454 μM. Among them, H1, H2, and H3 showed ideal pharmacodynamic effects on methicillin-resistant S. aureus ATCC43300. The total protein level of H1, H2, and H3 reached 1.70, 1.77 and 1.54 g/l at 120 h of induction in the 5-l fermenter, respectively. They killed over 99.9% of pathogens within 1.5 h at 2× and 4× MIC. The post antibiotic effect of H1, H2 and H3 to S. aureus ATCC43300 was 2.94, 1.75 and 1.55 h at 2× MIC, which was similar with their original peptide NZ2114 (1.43 h) and vancomycin (1.72 h). The fractional inhibitory concentration index (FICI) indicated indifferent effects between H1, H2, H3 and vancomycin, ampicillin, rifampicin. Additionally, they had low hemolysis and high stability in different environments (temperature, pH, proteases, and saline ions). All results indicate that H1, H2, and H3 can be produced in large-scale and have potential as therapeutic drugs against MRSA.Electronic supplementary materialThe online version of this article (doi:10.1186/s13568-017-0345-x) contains supplementary material, which is available to authorized users.

Design and Pharmacodynamics of Recombinant Fungus Defensin NZL with Improved Activity against Staphylococcus hyicus In Vitro and In Vivo

“…Time-kill curves were performed to assess the bactericidal rates of peptides against S. hyicus NCTC 10350 [ 25 ]. Simply, the mid-log phase of S. hyicus NCTC 10350 cells were diluted to 1 × 10 5 CFU/mL with MHB and incubated with NZL or NZ2114 with the final concentration of 1×, 2×, or 4× MIC.…”

“…For instance, MP1102, a variant mutated at three sites (N9Q, L13V and R14K) of NZ2114, was designed by increasing α-helicity index and hydrophobic moment, which exerted more potent activity (MIC = 0.04 to 0.23 μM) against MRSA than the parent peptide NZ2114 (MIC = 0.11 to 0.90 μM) [ 24 ]. Besides, NZ2114 derivatives (H1–H8) displayed improved activity and longer post-antibiotic effect (PAE) against S. aureus through substitution of His16 and His18 with Arg and Lys residues [ 25 ]. Therefore, simplification and design of variants are the optimal ways to obtain safe and efficient novel antimicrobial agents.…”

Overview of Host Defense Peptides and Their Applications for Plastic and Reconstructive Surgeons

“…[109][110][111] While commercial development was halted, preclinical studies are actively ongoing with promising results. [112][113][114][115][116] Oragenics (Tampa, FL, USA) has investigated…”

Internalization, distribution, and activity of peptide H2 against the intracellular multidrug-resistant bovine mastitis-causing bacterium Staphylococcus aureus

“…However, NZ2114 and MP1102 are more toxic towards mouse macrophages than vancomycin due to their high hydrophobicity 22 . Therefore, in our previous study, H2 (H18R), a novel NZ2114-derived peptide, was designed by replacing the histidine at position 16 with arginine to reduce its cytotoxicity; the results showed that H2 almost retained its original antibacterial activity against S. aureus and showed high stability in different environments 24 . Therefore, it is speculated that H2 may serve as a potential antibacterial agent against infections caused by S. aureus .…”