First report on rapid screening of nanomaterial-based antimicrobial agents against β-lactamase resistance using pGLO plasmid transformed Escherichia coli HB 101 K-12

Abstract

Combating antibiotic resistance requires discovery of novel antimicrobials effective against resistant bacteria. Herein, we present for the first time, pGLO plasmid transformed Escherichia coli HB 101 K 12 as novel model for screening of nanomaterial-based antimicrobial agents against b-lactamase resistance. E. coli HB 101 was transformed by pGLO plasmid in the presence of calcium chloride (50 mM; pH 6.1) aided by heat shock (0-42-0°C). The transformed bacteria were grown on Luria-Bertani agar containing ampicillin (amp) and arabinose (ara). The transformed culture was able to grow in the presence of ampicillin and also exhibited fluorescence under UV light. Both untransformed and transformed bacteria were used for screening citrate-mediated nanosilver (CNS), aloin-mediated nanosilver (ANS), 11-a-ketoboswellic acid (AKBA)-mediated nanosilver (BNS); nanozinc oxide, nanomanganese oxide (NMO) and phytochemicals such as aloin and AKBA. Minimum inhibitory concentrations (MIC) were obtained by microplate method using q-iodo nitro tetrazolium indicator. All the compounds were effective against transformed bacteria except NMO and AKBA. Transformed bacteria exhibited reverse cross resistance against aloin. ANS showed the highest antibacterial activity with a MIC of 0.32 ppm followed by BNS (10.32 ppm), CNS (20.64 ppm) and NZO (34.83 ppm). Thus, pGLO plasmid can be used to induce resistance against b-lactam antibiotics and the model can be used for rapid screening of new antibacterial agents effective against resistant bacteria.

Evaluation of the wound healing efficacy of chemical and phytogenic silver nanoparticles

“…NS is reported to have potent antibacterial effect against many bacterial species [19][20][21]. A previous study reported that NS dressing protects from bacterial contamination in a variety of chronic non-healing wounds.…”

“…The synthesis of nano-particles using various microbes and plant was explored [18][19][20][21]. The biosynthesis of nanoparticles using plant extracts produces green, eco-friendly nanoparticles and also exploits vast plant resources that are widely distributed, easily available, safe to handle and with a range of metabolites [22].…”

Antibacterial, anti‐inflammatory and antioxidant effects of acetyl‐11‐α‐keto‐β‐boswellic acid mediated silver nanoparticles in experimental murine mastitis

“…The production of silver, zinc and copper oxide nanoparticles is between 100 and 1000 tons per year globally [7]. Especially, silver nanoparticles (AgNPs) provide enormous hope for use in the medical field by virtue of their broad antimicrobial spectrum against both Gram positive and Gram negative bacteria, including multi‐drug resistant strains [8, 9] and relative non‐toxicity [10]. AgNPs are an attractive choice for therapy in mastitis as bacterial resistance is altogether absent [11, 12].…”