1
|
Tasdemiroglu Y, Council-Troche M, Chen M, Ledford B, Norris RA, Poelzing S, Gourdie RG, He JQ. Degradation of the α-Carboxyl Terminus 11 Peptide: In Vivo and Ex Vivo Impacts of Time, Temperature, Inhibitors, and Gender in Rat. ACS Pharmacol Transl Sci 2024; 7:1624-1636. [PMID: 38751644 PMCID: PMC11091968 DOI: 10.1021/acsptsci.4c00120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2024] [Revised: 04/03/2024] [Accepted: 04/08/2024] [Indexed: 05/18/2024]
Abstract
In previous research, a synthetic α-carboxyl terminus 1 (αCT1) peptide derived from connexin 43 (Cx43) and its variant (αCT11) showed beneficial effects in an ex vivo ischemia-reperfusion (I/R) heart injury model in mouse. In an in vivo mouse model of cryo-induced ventricular injury, αCT1 released from adhesive cardiac patches reduced Cx43 remodeling and arrhythmias, as well as maintained cardiac conduction. Whether intravenous injection of αCT1 or αCT11 produces similar outcomes has not been investigated. Given the possibility of peptide degradation in plasma, this study utilized in vivo I/R cardiac injury and ex vivo blood plasma models to examine factors that may limit the therapeutic potential of peptide therapeutics in vivo. Following tail vein administration of αCT11 (100 μM) in blood, no effect on I/R infarct size was observed in adult rat hearts on day 1 (D1) and day 28 (D28) after injury (p > 0.05). There was also no difference in the echocardiographic ejection fraction (EF%) between the control and the αCT11 groups (p > 0.05). Surprisingly, αCT11 in blood plasma collected from these rats was undetectable within ∼10 min after tail vein injection. To investigate factors that may modulate αCT11 degradation in blood, αCT11 was directly added to blood plasma isolated from normal rats without I/R and peptide levels were measured under different experimental conditions. Consistent with in vivo observations, significant αCT11 degradation occurred in plasma within 10 min at 22 and 37 °C and was nearly undetectable by 30 min. These responses were reduced by the addition of protease/phosphatase (PTase/PPTase) inhibitors to the isolated plasma. Interestingly, no significant differences in αCT11 degradation in plasma were noted between male and female rats. We conclude that fast degradation of αCT11 is likely the reason that no beneficial effects were observed in the in vivo I/R model and inhibition or shielding from PTase/PPTase activity may be a strategy that will assist with the viability of peptide therapeutics.
Collapse
Affiliation(s)
- Yagmur Tasdemiroglu
- Department
of Biomedical Sciences and Pathobiology, College of Veterinary Medicine, Virginia Tech, 225 Duck Pond Drive, Blacksburg, Virginia 24061, United States
| | - McAlister Council-Troche
- Department
of Biomedical Sciences and Pathobiology, College of Veterinary Medicine, Virginia Tech, 225 Duck Pond Drive, Blacksburg, Virginia 24061, United States
| | - Miao Chen
- Department
of Biomedical Sciences and Pathobiology, College of Veterinary Medicine, Virginia Tech, 225 Duck Pond Drive, Blacksburg, Virginia 24061, United States
| | - Benjamin Ledford
- Department
of Biomedical Sciences and Pathobiology, College of Veterinary Medicine, Virginia Tech, 225 Duck Pond Drive, Blacksburg, Virginia 24061, United States
| | - Russell A. Norris
- Department
of Medicine, Medical University of South
Carolina, Charleston, South Carolina 29425, United States
| | - Steven Poelzing
- Center
for Vascular and Heart Research, Fralin Biomedical Research Institute, Virginia Tech, 2 Riverside Circle, Roanoke, Virginia 24016, United States
| | - Robert G. Gourdie
- Center
for Vascular and Heart Research, Fralin Biomedical Research Institute, Virginia Tech, 2 Riverside Circle, Roanoke, Virginia 24016, United States
| | - Jia-Qiang He
- Department
of Biomedical Sciences and Pathobiology, College of Veterinary Medicine, Virginia Tech, 225 Duck Pond Drive, Blacksburg, Virginia 24061, United States
| |
Collapse
|
2
|
Wu D, Fu L, Cao Y, Dong N, Li D. Genomic insights into antimicrobial potential and optimization of fermentation conditions of pig-derived Bacillus subtilis BS21. Front Microbiol 2023; 14:1239837. [PMID: 37840708 PMCID: PMC10570807 DOI: 10.3389/fmicb.2023.1239837] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Accepted: 09/14/2023] [Indexed: 10/17/2023] Open
Abstract
Bacillus spp. have been widely used as probiotic supplements in animal feed as alternatives to antibiotics. In the present study, we screened a Bacillus subtilis strain named BS21 from pig feces. Antimicrobial activities, whole genome mining and UHPLC-MS/MS analysis were used to explore its antimicrobial mechanism. Strain BS21 showed Significant growth inhibition against a variety of animal pathogens, including Escherichia coli, Salmonella enterica Pullorum, Salmonella enterica Typhimurium, Citrobacter rodentium, Shigella flexneri and Staphylococcus aureus. Seven gene clusters involved in antimicrobial biosynthesis of secondary metabolites were encoded by strain BS21 genome, including four non-ribosomal peptides (bacillibactin, fengycin, surfactin and zwittermicin A), one ribosomal peptide (subtilosin A), one dipeptide (bacilysin) and one polyketide (bacillaene). Among them, production of surfactin, fengycin, bacillibactin, bacilysin and bacillaene was detected in the supernatant of B. subtilis strain BS21. To develop the potential application of BS21 in animal production, medium components and fermentation parameters optimization was carried out using response surface methodology (RSM). Production of antimicrobial secondary metabolites of strain BS21 was increased by 43.4%, and the best medium formula after optimization was corn flour 2%, soybean meal 1.7% and NaCl 0.5% with optimum culture parameters of initial pH 7.0, temperature 30°C, rotating speed at 220 rpm for 26 h. Our results suggested that strain BS21 has the potential for large-scale production and application as a potential source of probiotics and alternative to antibiotics for animal production.
Collapse
Affiliation(s)
| | | | | | - Na Dong
- State Key Laboratory of Animal Nutrition, College of Animal Science and Technology, China Agricultural University, Beijing, China
| | - Defa Li
- State Key Laboratory of Animal Nutrition, College of Animal Science and Technology, China Agricultural University, Beijing, China
| |
Collapse
|
3
|
Lin D, Sutherland D, Aninta SI, Louie N, Nip KM, Li C, Yanai A, Coombe L, Warren RL, Helbing CC, Hoang LMN, Birol I. Mining Amphibian and Insect Transcriptomes for Antimicrobial Peptide Sequences with rAMPage. Antibiotics (Basel) 2022; 11:antibiotics11070952. [PMID: 35884206 PMCID: PMC9312091 DOI: 10.3390/antibiotics11070952] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 07/12/2022] [Accepted: 07/13/2022] [Indexed: 02/01/2023] Open
Abstract
Antibiotic resistance is a global health crisis increasing in prevalence every day. To combat this crisis, alternative antimicrobial therapeutics are urgently needed. Antimicrobial peptides (AMPs), a family of short defense proteins, are produced naturally by all organisms and hold great potential as effective alternatives to small molecule antibiotics. Here, we present rAMPage, a scalable bioinformatics discovery platform for identifying AMP sequences from RNA sequencing (RNA-seq) datasets. In our study, we demonstrate the utility and scalability of rAMPage, running it on 84 publicly available RNA-seq datasets from 75 amphibian and insect species—species known to have rich AMP repertoires. Across these datasets, we identified 1137 putative AMPs, 1024 of which were deemed novel by a homology search in cataloged AMPs in public databases. We selected 21 peptide sequences from this set for antimicrobial susceptibility testing against Escherichia coli and Staphylococcus aureus and observed that seven of them have high antimicrobial activity. Our study illustrates how in silico methods such as rAMPage can enable the fast and efficient discovery of novel antimicrobial peptides as an effective first step in the strenuous process of antimicrobial drug development.
Collapse
Affiliation(s)
- Diana Lin
- Canada’s Michael Smith Genome Sciences Centre at BC Cancer, Vancouver, BC V5Z 4S6, Canada; (D.L.); (D.S.); (S.I.A.); (N.L.); (K.M.N.); (C.L.); (A.Y.); (L.C.); (R.L.W.)
| | - Darcy Sutherland
- Canada’s Michael Smith Genome Sciences Centre at BC Cancer, Vancouver, BC V5Z 4S6, Canada; (D.L.); (D.S.); (S.I.A.); (N.L.); (K.M.N.); (C.L.); (A.Y.); (L.C.); (R.L.W.)
- British Columbia Centre for Disease Control, Public Health Laboratory, Vancouver, BC V6Z R4R, Canada;
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Sambina Islam Aninta
- Canada’s Michael Smith Genome Sciences Centre at BC Cancer, Vancouver, BC V5Z 4S6, Canada; (D.L.); (D.S.); (S.I.A.); (N.L.); (K.M.N.); (C.L.); (A.Y.); (L.C.); (R.L.W.)
| | - Nathan Louie
- Canada’s Michael Smith Genome Sciences Centre at BC Cancer, Vancouver, BC V5Z 4S6, Canada; (D.L.); (D.S.); (S.I.A.); (N.L.); (K.M.N.); (C.L.); (A.Y.); (L.C.); (R.L.W.)
| | - Ka Ming Nip
- Canada’s Michael Smith Genome Sciences Centre at BC Cancer, Vancouver, BC V5Z 4S6, Canada; (D.L.); (D.S.); (S.I.A.); (N.L.); (K.M.N.); (C.L.); (A.Y.); (L.C.); (R.L.W.)
- Bioinformatics Graduate Program, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Chenkai Li
- Canada’s Michael Smith Genome Sciences Centre at BC Cancer, Vancouver, BC V5Z 4S6, Canada; (D.L.); (D.S.); (S.I.A.); (N.L.); (K.M.N.); (C.L.); (A.Y.); (L.C.); (R.L.W.)
- Bioinformatics Graduate Program, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Anat Yanai
- Canada’s Michael Smith Genome Sciences Centre at BC Cancer, Vancouver, BC V5Z 4S6, Canada; (D.L.); (D.S.); (S.I.A.); (N.L.); (K.M.N.); (C.L.); (A.Y.); (L.C.); (R.L.W.)
| | - Lauren Coombe
- Canada’s Michael Smith Genome Sciences Centre at BC Cancer, Vancouver, BC V5Z 4S6, Canada; (D.L.); (D.S.); (S.I.A.); (N.L.); (K.M.N.); (C.L.); (A.Y.); (L.C.); (R.L.W.)
| | - René L. Warren
- Canada’s Michael Smith Genome Sciences Centre at BC Cancer, Vancouver, BC V5Z 4S6, Canada; (D.L.); (D.S.); (S.I.A.); (N.L.); (K.M.N.); (C.L.); (A.Y.); (L.C.); (R.L.W.)
| | - Caren C. Helbing
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC V8P 5C2, Canada;
| | - Linda M. N. Hoang
- British Columbia Centre for Disease Control, Public Health Laboratory, Vancouver, BC V6Z R4R, Canada;
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Inanc Birol
- Canada’s Michael Smith Genome Sciences Centre at BC Cancer, Vancouver, BC V5Z 4S6, Canada; (D.L.); (D.S.); (S.I.A.); (N.L.); (K.M.N.); (C.L.); (A.Y.); (L.C.); (R.L.W.)
- British Columbia Centre for Disease Control, Public Health Laboratory, Vancouver, BC V6Z R4R, Canada;
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
- Correspondence:
| |
Collapse
|
4
|
Optimized peptide extraction method for analysis of antimicrobial peptide Kn2-7/dKn2-7 stability in human serum by LC-MS. Future Sci OA 2022; 8:FSO807. [PMID: 35909998 PMCID: PMC9327644 DOI: 10.2144/fsoa-2022-0013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Accepted: 06/16/2022] [Indexed: 11/23/2022] Open
Abstract
Aim: To develop an extraction protocol and determine stability for antimicrobial peptide (AMP) Kn2-7 and its d-enantiomer dKn2-7 in human serum. Materials & methods: We compared use of ethanol, acetonitrile, RapiGest SF Surfactant and 1% formic acid in ethanol for AMP recovery from serum prior to liquid chromatography-mass spectrometry quantification. Results: Precipitation of samples with 1% formic acid in ethanol caused the least amount of AMP loss during extraction from serum. Time-course experiments revealed dKn2-7 was significantly more stable than Kn2-7 in 25% serum, with 78.5% of dKn2-7 and only 1.0% of Kn2-7 remaining after 24 h at 37°C. Conclusion: The optimized method significantly increased peptide recovery and allowed more accurate and consistent quantification of Kn2-7 and dKn2-7 serum stability. Antimicrobial peptides are a new class of molecules being studied for treatment of infections. These peptides can easily be broken down by enzymes present in the body. Removal of the peptides by the enzymes might limit the effect of the drugs against an infection. Our work discusses the importance of testing the stability of these peptides in human serum, a bodily fluid that contains a large amount of enzymes. We describe a method to decrease loss of two potential peptide drugs during sample processing. Further, we report results of testing the stability of these two peptide drugs in human serum. Peptide extraction was optimized for maximum recovery of antimicrobial peptides Kn2-7/dKn2-7 from serum for LC–MS analysis. Time course experiments revealed d-amino acid analogue antimicrobial peptides were more stable against host proteases.
Collapse
|
5
|
McDaniel JS, Scott LLF, Rebeles J, Bramblett GT, Eriksson E, Johnson AJ, Griffith GL. Treatment of Corneal Infections Utilizing an Ocular Wound Chamber. Transl Vis Sci Technol 2020; 9:4. [PMID: 33200046 PMCID: PMC7645231 DOI: 10.1167/tvst.9.12.4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Accepted: 07/31/2020] [Indexed: 01/02/2023] Open
Abstract
Purpose To demonstrate that the ocular wound chamber (OWC) can be used for the treatment of bacterial keratitis (BK). Methods A blepharotomy was performed on anesthetized, hairless guinea pigs to induce exposure keratopathy 72 hours before corneal wound creation and Pseudomonas aeruginosa inoculation. Twenty-four hours postinoculation, eyes were treated with an OWC filled with 500 µL 0.5% moxifloxacin hydrochloride ophthalmic solution (OWC), 10 µL 0.5% moxifloxacin hydrochloride drops (DROPS) four times daily, or not treated (NT). White light, fluorescein, and spectral domain optical coherence tomography (SD-OCT) images; ocular and periocular tissues samples for colony-forming units (CFU) quantification; and plasma samples were collected at 24 and 72 hours posttreatment. Results White light, fluorescein, and SD-OCT imaging suggests OWC-treated eyes are qualitatively healthier than those in DROPS or NT groups. At 24 hours, the median number of CFUs (interquartile range) measured was 0 (0-8750), 150,000 (106,750-181,250), and 8750 (2525-16,000) CFU/mL for OWC, NT, and DROPS, respectively. While 100% of NT and DROPS animals remained infected at 24 hours, only 25% of OWC-treated animals showed infection. Skin samples at 24 hours showed infection percentages of 50%, 75%, and 0% in DROPS, NT, and OWC groups, respectively. OWC-treated animals had higher moxifloxacin plasma concentrations at 24 and 72 hours than those treated with drops. Conclusions OWC use resulted in a more rapid decrease of CFUs when compared to DROPS or NT groups and was associated with qualitatively healthier ocular and periocular tissue. Translational Relevance The OWC could be used clinically to continuously and rapidly deliver antimicrobials to infected ocular and periocular tissues, effectively lowering bacterial bioburdens and mitigating long-term complications.
Collapse
Affiliation(s)
- Jennifer S McDaniel
- Laulima Government Solutions, LLC, c/o Sensory Trauma, United States Army Institute of Surgical Research, San Antonio, TX, USA
| | - Laura L F Scott
- Epidemiology and Biostatistics Branch, United States Army Institute of Surgical Research, San Antonio, TX, USA
| | - Jennifer Rebeles
- BioAffinity Technologies, Science Research Laboratories (SRL) 1.424, San Antonio, TX, USA
| | - Gregory T Bramblett
- Department of Sensory Trauma, United States Army Institute of Surgical Research, San Antonio, TX, USA
| | | | - Anthony J Johnson
- Department of Sensory Trauma, United States Army Institute of Surgical Research, San Antonio, TX, USA
| | - Gina L Griffith
- Department of Sensory Trauma, United States Army Institute of Surgical Research, San Antonio, TX, USA
| |
Collapse
|
6
|
Caflisch KM, Suh GA, Patel R. Biological challenges of phage therapy and proposed solutions: a literature review. Expert Rev Anti Infect Ther 2019; 17:1011-1041. [PMID: 31735090 DOI: 10.1080/14787210.2019.1694905] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Introduction: In light of the emergence of antibiotic-resistant bacteria, phage (bacteriophage) therapy has been recognized as a potential alternative or addition to antibiotics in Western medicine for use in humans.Areas covered: This review assessed the scientific literature on phage therapy published between 1 January 2007 and 21 October 2019, with a focus on the successes and challenges of this prospective therapeutic.Expert opinion: Efficacy has been shown in animal models and experimental findings suggest promise for the safety of human phagotherapy. Significant challenges remain to be addressed prior to the standardization of phage therapy in the West, including the development of phage-resistant bacteria; the pharmacokinetic complexities of phage; and any potential human immune response incited by phagotherapy.
Collapse
Affiliation(s)
- Katherine M Caflisch
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN, USA
| | - Gina A Suh
- Division of Infectious Diseases, Department of Medicine, Mayo Clinic, Rochester, MN, USA
| | - Robin Patel
- Division of Infectious Diseases, Department of Medicine, Mayo Clinic, Rochester, MN, USA.,Division of Clinical Microbiology, Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
| |
Collapse
|
7
|
Oh Y, Lai JSY, Mills HJ, Erdjument-Bromage H, Giammarinaro B, Saadipour K, Wang JG, Abu F, Neubert TA, Suh GSB. A glucose-sensing neuron pair regulates insulin and glucagon in Drosophila. Nature 2019; 574:559-564. [PMID: 31645735 PMCID: PMC6857815 DOI: 10.1038/s41586-019-1675-4] [Citation(s) in RCA: 65] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Accepted: 09/16/2019] [Indexed: 01/08/2023]
Abstract
Although glucose-sensing neurons were identified more than 50 years ago, the physiological role of glucose sensing in metazoans remains unclear. Here we identify a pair of glucose-sensing neurons with bifurcated axons in the brain of Drosophila. One axon branch projects to insulin-producing cells to trigger the release of Drosophila insulin-like peptide 2 (dilp2) and the other extends to adipokinetic hormone (AKH)-producing cells to inhibit secretion of AKH, the fly analogue of glucagon. These axonal branches undergo synaptic remodelling in response to changes in their internal energy status. Silencing of these glucose-sensing neurons largely disabled the response of insulin-producing cells to glucose and dilp2 secretion, disinhibited AKH secretion in corpora cardiaca and caused hyperglycaemia, a hallmark feature of diabetes mellitus. We propose that these glucose-sensing neurons maintain glucose homeostasis by promoting the secretion of dilp2 and suppressing the release of AKH when haemolymph glucose levels are high.
Collapse
Affiliation(s)
- Yangkyun Oh
- Skirball Institute of Biomolecular Medicine, Department of Cell Biology, Neuroscience Institute, New York University School of Medicine, New York, NY, USA
| | - Jason Sih-Yu Lai
- Skirball Institute of Biomolecular Medicine, Department of Cell Biology, Neuroscience Institute, New York University School of Medicine, New York, NY, USA
- QPS-Qualitix Taiwan, Ren-Ai Road, Taipei, Taiwan
| | - Holly J Mills
- Skirball Institute of Biomolecular Medicine, Department of Cell Biology, Neuroscience Institute, New York University School of Medicine, New York, NY, USA
- Ascend Public Charter Schools, New York, NY, USA
| | - Hediye Erdjument-Bromage
- Skirball Institute of Biomolecular Medicine, Department of Cell Biology, Neuroscience Institute, New York University School of Medicine, New York, NY, USA
| | - Benno Giammarinaro
- Skirball Institute of Biomolecular Medicine, Department of Cell Biology, Neuroscience Institute, New York University School of Medicine, New York, NY, USA
- Vision Sciences Graduate Program, School of Optometry, UC Berkeley, Berkeley, CA, USA
| | - Khalil Saadipour
- Skirball Institute of Biomolecular Medicine, Department of Cell Biology, Neuroscience Institute, New York University School of Medicine, New York, NY, USA
| | - Justin G Wang
- Skirball Institute of Biomolecular Medicine, Department of Cell Biology, Neuroscience Institute, New York University School of Medicine, New York, NY, USA
- Salk Institute for Biological Studies, La Jolla, CA, USA
| | - Farhan Abu
- Skirball Institute of Biomolecular Medicine, Department of Cell Biology, Neuroscience Institute, New York University School of Medicine, New York, NY, USA
- Department of Genetics and Development, Columbia University, New York, NY, USA
| | - Thomas A Neubert
- Skirball Institute of Biomolecular Medicine, Department of Cell Biology, Neuroscience Institute, New York University School of Medicine, New York, NY, USA
| | - Greg S B Suh
- Skirball Institute of Biomolecular Medicine, Department of Cell Biology, Neuroscience Institute, New York University School of Medicine, New York, NY, USA.
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, South Korea.
| |
Collapse
|
8
|
Construction of a genetically modified T7Select phage system to express the antimicrobial peptide 1018. J Microbiol 2019; 57:532-538. [PMID: 31054139 DOI: 10.1007/s12275-019-8686-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Revised: 01/10/2019] [Accepted: 01/29/2019] [Indexed: 12/20/2022]
Abstract
Bacteriophage therapy was an ascendant technology for combating bacterial infections before the golden age of antibiotics, but the therapeutic potential of phages was largely ignored after the discovery of penicillin. Recently, with antibiotic-resistant infections on the rise, these phages are receiving renewed attention to combat problematic bacterial infections. Our approach is to enhance bacteriophages with antimicrobial peptides, short peptides with broad-spectrum antibiotic or antibiofilm effects. We inserted coding sequences for 1018, an antimicrobial peptide previously shown to be an effective broad-spectrum antimicrobial and antibiofilm agent, or the fluorescent marker mCherry, into the T7Select phage genome. Transcription and production of 1018 or mCherry began rapidly alter E. coli cultures were infected with genetically modified phages. mCherry fluorescence, which requires a 90 min initial maturation period, was observed in infected cultures after 2 h of infection. Finally, we tested phages expressing 1018 (1018 T7) against bacterial planktonic cultures and biofilms, and found the 1018 T7 phage was more effective than the unmodified T7Select phage at both killing planktonic cells and eradicating established biofilms, validating our phage-driven antimicrobial peptide expression system. The combination of narrow-spectrum phages delivering relatively high local doses of broad-spectrum antimicrobials could be a powerful method to combat resistant infections. The experiments we describe prove this combination is feasible in vitro, but further testing and optimization are required before genetically modified phages are ready for use in vivo.
Collapse
|