scholarly journals Fabrication of Antimicrobial Peptide-Loaded PLGA/Chitosan Composite Microspheres for Long-Acting Bacterial Resistance

Molecules ◽  
2017 ◽  
Vol 22 (10) ◽  
pp. 1637 ◽  
Author(s):  
Yuanyuan Li ◽  
Rongwei Na ◽  
Xiumei Wang ◽  
Huiying Liu ◽  
Lingyun Zhao ◽  
...  
Keyword(s):  
Antimicrobial Peptide ◽  
Bacterial Resistance ◽  
Composite Microspheres ◽  
Long Acting ◽  
Chitosan Composite

An Investigation of Two Kinds of Magnetic Chitosan Composite Microspheres

2007 ◽  
Vol 22 (4) ◽  
pp. 429-441 ◽  
Author(s):  
Ji Zhang ◽  
Shengtang Zhang ◽  
Guangpeng Wu ◽  
Wenqiang Wang ◽  
Sufang Gao ◽  
...  
Keyword(s):  
Magnetic Chitosan ◽  
Composite Microspheres ◽  
Chitosan Composite

Preparation, Characterization and In Vitro Release Kinetics of Vancomycin Carried β-TCP/Chitosan Composite Microspheres Used as Bone Tissue Engineering Scaffolds

2012 ◽  
Vol 512-515 ◽  
pp. 1821-1825
Author(s):  
Lin Zhang ◽  
Xue Min Cui ◽  
Qing Feng Zan ◽  
Li Min Dong ◽  
Chen Wang ◽  
...  
Keyword(s):  
Tissue Engineering ◽  
Release Kinetics ◽  
In Vitro Release ◽  
Cross Linking ◽  
Tissue Engineering Scaffolds ◽  
Composite Microspheres ◽  
Chitosan Composite ◽  
Vitro Release

A novel microsphere scaffolds composed of chitosan and β-TCP containing vancomycin was designed and prepared. The β-TCP/chitosan composite microspheres were prepared by solid-in-water-in-oil (s/w/o) emulsion cross-linking method with or without pre-cross-linking process. The mode of vancomycin maintaining in the β-TCP/chitosan composite microspheres was detected by Fourier transform infrared spectroscopy (FTIR). The in vitro release curve of vancomycin in simulated body fluid (SBF) was estimated. The results revealed that the pre-cross-linking prepared microspheres possessed higher loading efficiency (LE) and encapsulation efficiency (EE) especially decreasing the previous burst mass of vancomycin in incipient release. These composite microspheres got excellent sphere and well surface roughness in morphology. Vancomycin was encapsulated in composite microspheres through absorption and cross-linking. While in-vitro release curves illustrated that vancomycin release depond on diffusing firstly and then on the degradation ratio later. The microspheres loading with vancomycin would be to restore bone defect, meanwhile to inhibit bacterium proliferation. These bioactive, degradable composite microspheres have potential applications in 3D tissue engineering of bone and other tissues in vitro and in vivo.

scholarly journals Experimental Induction of Bacterial Resistance to the Antimicrobial Peptide Tachyplesin I and Investigation of the Resistance Mechanisms

2016 ◽  
Vol 60 (10) ◽  
pp. 6067-6075 ◽  
Author(s):  
Jun Hong ◽  
Jianye Hu ◽  
Fei Ke
Keyword(s):  
Antimicrobial Peptide ◽  
Bacterial Resistance ◽  
Antimicrobial Agents ◽  
Resistance Mechanisms ◽  
Cross Resistance ◽  
Antibacterial Drug ◽  
Cationic Antimicrobial Peptide ◽  
Content Type ◽  
Tachyplesin I

ABSTRACTTachyplesin I is a 17-amino-acid cationic antimicrobial peptide (AMP) with a typical cyclic antiparallel β-sheet structure that is a promising therapeutic for infections, tumors, and viruses. To date, no bacterial resistance to tachyplesin I has been reported. To explore the safety of tachyplesin I as an antibacterial drug for wide clinical application, we experimentally induced bacterial resistance to tachyplesin I by using two selection procedures and studied the preliminary resistance mechanisms.Aeromonas hydrophilaXS91-4-1,Pseudomonas aeruginosaCGMCC1.2620, andEscherichia coliATCC 25922 and F41 showed resistance to tachyplesin I under long-term selection pressure with continuously increasing concentrations of tachyplesin I. In addition,P. aeruginosaandE. coliexhibited resistance to tachyplesin I under UV mutagenesis selection conditions. Cell growth and colony morphology were slightly different between control strains and strains with induced resistance. Cross-resistance to tachyplesin I and antimicrobial agents (cefoperazone and amikacin) or other AMPs (pexiganan, tachyplesin III, and polyphemusin I) was observed in some resistant mutants. Previous studies showed that extracellular protease-mediated degradation of AMPs induced bacterial resistance to AMPs. Our results indicated that the resistance mechanism ofP. aeruginosawas not entirely dependent on extracellular proteolytic degradation of tachyplesin I; however, tachyplesin I could induce increased proteolytic activity inP. aeruginosa. Most importantly, our findings raise serious concerns about the long-term risks associated with the development and clinical use of tachyplesin I.

Modification of a derived antimicrobial peptide on steel surface for marine bacterial resistance

2020 ◽  
Vol 510 ◽  
pp. 145512 ◽  
Author(s):  
Pan Cao ◽  
Chongwei Du ◽  
Xiaoyan He ◽  
Chao Zhang ◽  
Chengqing Yuan
Keyword(s):  
Antimicrobial Peptide ◽  
Steel Surface ◽  
Bacterial Resistance

scholarly journals A Protein Important for Antimicrobial Peptide Resistance, YdeI/OmdA, Is in the Periplasm and Interacts with OmpD/NmpC

2009 ◽  
Vol 191 (23) ◽  
pp. 7243-7252 ◽  
Author(s):  
M. Carolina Pilonieta ◽  
Kimberly D. Erickson ◽  
Robert K. Ernst ◽  
Corrella S. Detweiler
Keyword(s):  
Gene Expression ◽  
Antimicrobial Peptide ◽  
Bacterial Resistance ◽  
Cell Types ◽  
Polymyxin B ◽  
Sensor Kinase ◽  
Multiple Cell ◽  
Ob Fold ◽  
Antimicrobial Peptide Resistance ◽  
Multicellular Organisms

ABSTRACT Antimicrobial peptides (AMPs) kill or prevent the growth of microbes. AMPs are made by virtually all single and multicellular organisms and are encountered by bacteria in diverse environments, including within a host. Bacteria use sensor-kinase systems to respond to AMPs or damage caused by AMPs. Salmonella enterica deploys at least three different sensor-kinase systems to modify gene expression in the presence of AMPs: PhoP-PhoQ, PmrA-PmrB, and RcsB-RcsC-RcsD. The ydeI gene is regulated by the RcsB-RcsC-RcsD pathway and encodes a 14-kDa predicted oligosaccharide/oligonucleotide binding-fold (OB-fold) protein important for polymyxin B resistance in broth and also for virulence in mice. We report here that ydeI is additionally regulated by the PhoP-PhoQ and PmrA-PmrB sensor-kinase systems, which confer resistance to cationic AMPs by modifying lipopolysaccharide (LPS). ydeI, however, is not important for known LPS modifications. Two independent biochemical methods found that YdeI copurifies with OmpD/NmpC, a member of the trimeric β-barrel outer membrane general porin family. Genetic analysis indicates that ompD contributes to polymyxin B resistance, and both ydeI and ompD are important for resistance to cathelicidin antimicrobial peptide, a mouse AMP produced by multiple cell types and expressed in the gut. YdeI localizes to the periplasm, where it could interact with OmpD. A second predicted periplasmic OB-fold protein, YgiW, and OmpF, another general porin, also contribute to polymyxin B resistance. Collectively, the data suggest that periplasmic OB-fold proteins can interact with porins to increase bacterial resistance to AMPs.

Sign in / Sign up

Export Citation Format

Share Document