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Zhang G, Feng S, Qin M, Sun J, Liu Y, Luo C, Lin M, Xu S, Liao M, Fan H, Liang Z. Influence of PepF peptidase and sporulation on microcin J25 production in Bacillus subtilis. Microbiol Spectr 2024; 12:e0374823. [PMID: 38780256 PMCID: PMC11218540 DOI: 10.1128/spectrum.03748-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Accepted: 04/12/2024] [Indexed: 05/25/2024] Open
Abstract
The lasso peptide microcin J25 (MccJ25) possesses strong antibacterial properties and is considered a potential effective component of bacterial disease treatment drugs and safe food preservatives. Although MccJ25 can be heterologously expressed in Bacillus subtilis as we have previously reported, its regulation and accumulation are yet to be understood. Here, we investigated the expression level and stability of MccJ25 in B. subtilis strains with disruption in peptidase genes pepA, pepF, and pepT. Oligoendopeptidase F (PepF) was found to be involved in reduction of the production of MccJ25 by degradation of its precursor peptide. In the pepF mutant, the MccJ25 reached a concentration of 1.68 µM after a cultivation time exceeding 60 hours, while the wild-type strain exhibited a concentration of only 0.14 µM. Moreover, the production of MccJ25 in B. subtilis downregulated the genes associated with sporulation, and this may contribute to its accumulation. Finally, this study provides a strategy to improve the stability and production of MccJ25 in B. subtilis. IMPORTANCE MccJ25 displays significant antibacterial activity, a well-defined mode of action, exceptional safety, and remarkable stability. Hence, it presents itself as a compelling candidate for an optimal antibacterial or anti-endotoxin medication. The successful establishment of exogenous production of MccJ25 in Bacillus subtilis provides a strategy for reducing its production cost and diversifying its utilization. In this study, we have provided evidence indicating that both peptidase PepF and sporulation are significant factors that limit the expression of MccJ25 in B. subtilis. The ΔpepF and ΔsigF mutants of B. subtilis express MccJ25 with higher production yield and enhanced stability. To sum up, this study developed several better engineered strains of B. subtilis, which greatly reduced the consumption of MccJ25 during the nutrient depletion stage of the host strain, improved its production, and elucidated factors that may be involved in reducing MccJ25 accumulation in B. subtilis.
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Affiliation(s)
- Guangwen Zhang
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Saixiang Feng
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou, China
- Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Guangzhou, China
- Key Laboratory of Veterinary Vaccine Innovation of the Ministry of Agriculture, Guangzhou, China
- National and Regional Joint Engineering Laboratory for Medicament of Zoonosis Prevention and Control, Guangzhou, China
| | - Miaomiao Qin
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Juan Sun
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Yutong Liu
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Changqi Luo
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Min Lin
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Siqi Xu
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Ming Liao
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou, China
- Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Guangzhou, China
- Key Laboratory of Veterinary Vaccine Innovation of the Ministry of Agriculture, Guangzhou, China
- National and Regional Joint Engineering Laboratory for Medicament of Zoonosis Prevention and Control, Guangzhou, China
- Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou, China
| | - Huiying Fan
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou, China
- Key Laboratory of Veterinary Vaccine Innovation of the Ministry of Agriculture, Guangzhou, China
- National and Regional Joint Engineering Laboratory for Medicament of Zoonosis Prevention and Control, Guangzhou, China
| | - Zhaoping Liang
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
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Mirshahi S, Vahedi B, Yazdani SO, Golab M, Sazgarnia A. Calculating transmembrane voltage on the electric pulse-affected cancerous cell membrane: using molecular dynamics and finite element simulations. J Mol Model 2024; 30:221. [PMID: 38904863 DOI: 10.1007/s00894-024-06012-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2024] [Accepted: 06/07/2024] [Indexed: 06/22/2024]
Abstract
CONTEXT Electroporation is a technique that creates electrically generated pores in the cell membrane by modifying transmembrane potential. In this work, the finite element method (FEM) was used to examine the induced transmembrane voltage (ITV) of a spherical-shaped MCF-7 cell, allowing researchers to determine the stationary ITV. A greater ITV than the critical value causes permeabilization of the membrane. Furthermore, the present study shows how a specific surface conductivity can act as a stand-in for the thin layer that constitutes a cell membrane as the barrier between extracellular and intracellular environments. Additionally, the distribution of ITV on the cell membrane and its maximum value were experimentally evaluated for a range of applied electric fields. Consequently, the entire cell surface area was electroporated 66% and 68% for molecular dynamics (MD) simulations and FEM, respectively, when the external electric field of 1500 V/cm was applied to the cell suspension using the previously indicated numerical methods. Furthermore, the lipid bilayers' molecular structure was changed, which led to the development of hydrophilic holes with a radius of 1.33 nm. Applying MD and FEM yielded threshold values for transmembrane voltage of 700 and 739 mV, respectively. METHOD Using MD simulations of palmitoyloleoyl-phosphatidylcholine (POPC), pores in cell membranes exposed to external electric fields were numerically investigated. The dependence on the electric field was estimated and developed, and the amount of the electroporated cell surface area matches the applied external electric field. To investigate more, a mathematical model based on an adaptive neuro-fuzzy inference system (ANFIS) is employed to predict the percent cell viability of cancerous cells after applying four pulses during electroporation. For MD simulations, ArgusLab, VMD, and GROMACS software packages were used. Moreover, for FEM analysis, COMSOL software package was used. Also, it is worth mentioning that for mathematical model, MATLAB software is used.
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Affiliation(s)
- Salim Mirshahi
- Department of Mechanical Engineering, Sharif University of Technology, Tehran, Iran.
- Department of Mechanical Engineering, University of Connecticut, Storrs, United States of America.
| | - Behzad Vahedi
- Functional Neurosurgery Research Center, Shohada Tajrish Comprehensive Neurosurgical Center of Excellence, Shahid Beheshti University of Medical Sciences, Post Office Box: 1983969411, Tehran, Iran.
| | - Saeed Oraee Yazdani
- Functional Neurosurgery Research Center, Shohada Tajrish Comprehensive Neurosurgical Center of Excellence, Shahid Beheshti University of Medical Sciences, Post Office Box: 1983969411, Tehran, Iran.
| | - Mahdi Golab
- Department of Computer Engineering, Neyshabur Branch, Islamic Azad University, Neyshabur, Iran
| | - Ameneh Sazgarnia
- Medical Physics Research Center, Mashhad University of Medical Sciences, Mashhad, Iran.
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3
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Scharf A, La-Rostami F, Illarionov BA, Nemes V, Feldmann AM, Höft LS, Lösel H, Bacher A, Fischer M. Systematic Analysis of the Effect of Genomic Knock-Out of Non-Essential Promiscuous HAD-Like Phosphatases YcsE, YitU and YwtE on Flavin and Adenylate Content in Bacillus Subtilis. Chembiochem 2024; 25:e202400165. [PMID: 38616163 DOI: 10.1002/cbic.202400165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Revised: 04/05/2024] [Accepted: 04/09/2024] [Indexed: 04/16/2024]
Abstract
Studying the metabolic role of non-essential promiscuous enzymes is a challenging task, as genetic manipulations usually do not reveal at which point(s) of the metabolic network the enzymatic activity of such protein is beneficial for the organism. Each of the HAD-like phosphatases YcsE, YitU and YwtE of Bacillus subtilis catalyzes the dephosphorylation of 5-amino-6-ribitylamino-uracil 5'-phosphate, which is essential in the biosynthesis of riboflavin. Using CRISPR technology, we have found that the deletion of these genes, individually or in all possible combinations failed to cause riboflavin auxotrophy and did not result in significant growth changes. Analysis of flavin and adenylate content in B. subtilis knockout mutants showed that (i) there must be one or several still unidentified phosphatases that can replace the deleted proteins; (ii) such replacements, however, cannot fully restore the intracellular content of any of three flavins studied (riboflavin, FMN, FAD); (iii) whereas bacterial fitness was not significantly compromised by mutations, the intracellular balance of flavins and adenylates did show some significant changes.
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Affiliation(s)
- Alexandra Scharf
- Hamburg School of Food Science, Institute of Food Chemistry, University of Hamburg, Grindelallee 117, 20146, Hamburg, Germany
| | - Farshad La-Rostami
- Hamburg School of Food Science, Institute of Food Chemistry, University of Hamburg, Grindelallee 117, 20146, Hamburg, Germany
| | - Boris A Illarionov
- Hamburg School of Food Science, Institute of Food Chemistry, University of Hamburg, Grindelallee 117, 20146, Hamburg, Germany
| | - Vivien Nemes
- Hamburg School of Food Science, Institute of Food Chemistry, University of Hamburg, Grindelallee 117, 20146, Hamburg, Germany
| | - Anna M Feldmann
- Hamburg School of Food Science, Institute of Food Chemistry, University of Hamburg, Grindelallee 117, 20146, Hamburg, Germany
| | - Lars S Höft
- Hamburg School of Food Science, Institute of Food Chemistry, University of Hamburg, Grindelallee 117, 20146, Hamburg, Germany
| | - Henri Lösel
- Hamburg School of Food Science, Institute of Food Chemistry, University of Hamburg, Grindelallee 117, 20146, Hamburg, Germany
| | - Adelbert Bacher
- TUM School of Natural Sciences, Technical University of Munich, 85748, Garching, Germany
| | - Markus Fischer
- Hamburg School of Food Science, Institute of Food Chemistry, University of Hamburg, Grindelallee 117, 20146, Hamburg, Germany
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Kim EYS, Maltempi de Souza E, Müller-Santos M. Optimisation of DNA electroporation protocols for different plant-associated bacteria. J Microbiol Methods 2024; 220:106912. [PMID: 38452904 DOI: 10.1016/j.mimet.2024.106912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 03/04/2024] [Accepted: 03/04/2024] [Indexed: 03/09/2024]
Abstract
Electroporation is a vital process that facilitates the use of modern recombineering and other high-throughput techniques in a wide array of microorganisms, including non-model bacteria like plant growth-promoting bacteria (PGPB). These microorganisms play a significant role in plant health by colonizing plants and promoting growth through nutrient exchange and hormonal regulation. In this study, we introduce a sequential Design of Experiments (DOE) approach to obtain highly competent cells swiftly and reliably for electroporation. Our method focuses on optimizing the three stages of the electroporation procedure-preparing competent cells, applying the electric pulse field, and recovering transformed cells-separately. We utilized a split-plot fractional design with five factors and a covariate to optimize the first step, response surface methodology (RSM) for the second step, and Plackett-Burman design for two categorical factors and one continuous factor for the final step. Following the experimental sequence with three bacterial models, we achieved efficiencies 10 to 100 times higher, reaching orders of 105 to 106 CFU/μg of circular plasmid DNA. These results highlight the significant potential for enhancing electroporation protocols for non-model bacteria.
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Affiliation(s)
- Edson Yu Sin Kim
- Nitrogen Fixation Laboratory, Department of Biochemistry and Molecular Biology, Federal University of Paraná (UFPR), Curitiba, Brazil
| | - Emanuel Maltempi de Souza
- Nitrogen Fixation Laboratory, Department of Biochemistry and Molecular Biology, Federal University of Paraná (UFPR), Curitiba, Brazil
| | - Marcelo Müller-Santos
- Nitrogen Fixation Laboratory, Department of Biochemistry and Molecular Biology, Federal University of Paraná (UFPR), Curitiba, Brazil.
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5
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Mohamadzadeh M, Ghiasi M, Aghamollaei H. Optimization of plasmid electrotransformation into Bacillus subtilis using an antibacterial peptide. Arch Microbiol 2024; 206:116. [PMID: 38388903 DOI: 10.1007/s00203-024-03847-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 01/11/2024] [Accepted: 01/13/2024] [Indexed: 02/24/2024]
Abstract
Bacillus subtilis can potentially serve as an efficient expression host for biotechnology due to its ability to secrete extracellular proteins and enzymes directly into the culture medium. One of the important challenges in the biotechnology industry is to optimize the transformation conditions of B. subtilis bacteria. This study aims to provide a new method to optimize the transformation conditions and improve the transformation efficiency of B. subtilis WB600. To increase the transformation efficiency in B. subtilis, two methods of adding CM11 antibacterial peptides to the bacterial medium along with electroporation and optimizing the variables including the growth medium composition, time to adding CM11 peptide, electroporation voltage, recovery medium, and cell recovery time are used. The results of this study showed that the addition of antimicrobial peptides (AMPs) with a concentration of 2 μg/ml increases the transformation efficiency by 4 times compared to the absence of AMP in the bacterial medium. Additionally, the findings from our study indicated that the most optimal rate of transformation for B. subtilis was observed at a voltage of 7.5 kV/cm, with a recovery period of 12 h. With the optimized method, the transformation efficiency came up to 1.69 × 104 CFU/µg DNA. This improvement in transformation efficiency will be attributed to the research of expression of exogenous genes in B. subtilis, gene library construction for transformation of wild-type B. subtilis strains.
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Affiliation(s)
| | - Mohsen Ghiasi
- Rajaie Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran
- Department of Cellular and Molecular Biology, Faculty of Advanced Science and Technology, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
| | - Hossein Aghamollaei
- Chemical Injuries Research Center, Systems Biology and Poisonings Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran.
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Zhang G, Lin M, Qin M, Xie Q, Liang M, Jiang J, Dai H, Xu S, Feng S, Liao M. Establishing Heterologous Production of Microcins J25 and Y in Bacillus subtilis. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2023; 71:5600-5613. [PMID: 36995900 DOI: 10.1021/acs.jafc.3c00675] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
Microcin J25 (MccJ25) and microcin Y (MccY) are lasso peptides and considered potential alternatives to antibiotics and harmful preservatives. The combination of these two microcins can provide a wide antimicrobial spectrum against food-borne Salmonella. Currently, MccJ25 and MccY are produced using Escherichia coli expression systems; however, the entire production process is accompanied by negative effects from endotoxins. In this study, we identified Bacillus subtilis as a suitable host for MccJ25 and MccY production. High-level production of microcins was achieved by promoter optimization, host strain selection, and recombinant expression. The engineered strains produced maximum yields of 2.827 μM MccJ25 and 1.481 μM MccY. This is the first study to demonstrate the expression of MccJ25 and MccY in B. subtilis, and it offers a few engineered strains that are without antibiotic resistance markers, inducer-free, sporulation-deficient, and free of the negative effects of endotoxins for antibacterial therapy and food preservation.
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Affiliation(s)
- Guangwen Zhang
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, P. R. China
| | - Min Lin
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, P. R. China
| | - Miaomiao Qin
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, P. R. China
| | - Qianmei Xie
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, P. R. China
| | - Mingzhi Liang
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, P. R. China
| | - Jinfei Jiang
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, P. R. China
| | - Huilin Dai
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, P. R. China
| | - Siqi Xu
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, P. R. China
| | - Saixiang Feng
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, P. R. China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, P. R. China
- Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Guangzhou 510642, P. R. China
- Key Laboratory of Veterinary Vaccine Innovation of the Ministry of Agriculture, Guangzhou 510642, P. R. China
- National and Regional Joint Engineering Laboratory for Medicament of Zoonosis Prevention and Control, Guangzhou 510642, P. R. China
| | - Ming Liao
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, P. R. China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, P. R. China
- Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Guangzhou 510642, P. R. China
- Key Laboratory of Veterinary Vaccine Innovation of the Ministry of Agriculture, Guangzhou 510642, P. R. China
- National and Regional Joint Engineering Laboratory for Medicament of Zoonosis Prevention and Control, Guangzhou 510642, P. R. China
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Feng RY, Chen YH, Lin C, Tsai CH, Yang YL, Chen YL. Surfactin secreted by Bacillus amyloliquefaciens Ba01 is required to combat Streptomyces scabies causing potato common scab. FRONTIERS IN PLANT SCIENCE 2022; 13:998707. [PMID: 36388520 PMCID: PMC9664162 DOI: 10.3389/fpls.2022.998707] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Accepted: 10/17/2022] [Indexed: 06/16/2023]
Abstract
Potato common scab, which is mainly caused by the bacterium Streptomyces scabies, occurs in key potato growing regions worldwide. It causes necrotic or corky symptoms on potato tubers and decreases the economic value of potato. At present, there is no recommended chemical or biological control for combating potato common scab in Taiwan. It can only reduce the occurrence by cultivation control, but the efficacy is limited. Previously we found that Bacillus amyloliquefaciens Ba01 could control potato common scab in pot assay and in the field. The potential anti-S. scabies mechanism was associated with surfactin secretion, but further molecular dissection was not conducted. Thus, in this study we aimed to determine whether surfactin is the main compound active against S. scabies by knocking out the srf gene cluster in Ba01. The cloning plasmid pRY1 was transformed to Ba01 by electroporation for in-frame deletion. Two independent Δsrf mutants were obtained and confirmed by specific primers and mass spectrometry. The swarming ability and S. scabies inhibition was significantly decreased (P<0.001) in Δsrf mutants. The swarming ability of Δsrf mutants could be restored by the addition of surfactin. Furthermore, we found that Ba01 formed wrinkled biofilm in MSgg liquid medium, while Δsrf mutants formed biofilm abnormally. Furthermore, the α-amylase, protease and phosphate-solubilizing ability of Δsrf mutants was decreased, and the mutants could not inhibit the growth and sporulation of S. scabies on potato tuber slices. In conclusion, srf gene cluster of B. amyloliquefaciens Ba01 is responsible for the secretion of surfactin and inhibition of S. scabies.
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Affiliation(s)
- Ru-Ying Feng
- Master Program for Plant Medicine, National Taiwan University, Taipei, Taiwan
| | - Yi-Hsuan Chen
- Master Program for Plant Medicine, National Taiwan University, Taipei, Taiwan
| | - Chih Lin
- Department of Plant Pathology and Microbiology, National Taiwan University, Taipei, Taiwan
| | - Chia-Hsin Tsai
- Plant Pathology Division, Taiwan Agricultural Research Institute, Taichung, Taiwan
| | - Yu-Liang Yang
- Agricultural Biotechnology Research Center, Academia Sinica, Taipei, Taiwan
| | - Ying-Lien Chen
- Master Program for Plant Medicine, National Taiwan University, Taipei, Taiwan
- Department of Plant Pathology and Microbiology, National Taiwan University, Taipei, Taiwan
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Zhang K, Li S, Wang Y, Wang Z, Mulvenna N, Yang H, Zhang P, Chen H, Li Y, Wang H, Gao Y, Wigneshweraraj S, Matthews S, Zhang K, Liu B. Bacteriophage protein PEIP is a potent Bacillus subtilis enolase inhibitor. Cell Rep 2022; 40:111026. [PMID: 35793626 DOI: 10.1016/j.celrep.2022.111026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Revised: 04/26/2022] [Accepted: 06/09/2022] [Indexed: 11/03/2022] Open
Abstract
Enolase is a highly conserved enzyme that presents in all organisms capable of glycolysis or fermentation. Its immediate product phosphoenolpyruvate is essential for other important processes like peptidoglycan synthesis and the phosphotransferase system in bacteria. Therefore, enolase inhibitors are of great interest. Here, we report that Gp60, a phage-encoded enolase inhibitor protein (PEIP) of bacteriophage SPO1 for Bacillus subtilis, is an enolase inhibitor. PEIP-expressing bacteria exhibit growth attenuation, thinner cell walls, and safranin color in Gram staining owing to impaired peptidoglycan synthesis. We solve the structure of PEIP-enolase tetramer and show that PEIP disassembles enolase by disrupting the basic dimer unit. The structure reveals that PEIP does not compete for substrate binding but induces a cascade of conformational changes that limit accessibility to the enolase catalytic site. This phage-inspired disassembly of enolase represents an alternative strategy for the development of anti-microbial drugs.
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Affiliation(s)
- Kaining Zhang
- BioBank, The First Affiliated Hospital of Xi'an Jiaotong University, Shaanxi 710061, China; Institute for Protein Science and Phage Research, The First Affiliated Hospital of Xi'an Jiaotong University, Shaanxi 710061, China
| | - Shanshan Li
- MOE Key Laboratory for Cellular Dynamics and School of Life Sciences, University of Science and Technology of China, Hefei 230027, China
| | - Yawen Wang
- BioBank, The First Affiliated Hospital of Xi'an Jiaotong University, Shaanxi 710061, China; Institute for Protein Science and Phage Research, The First Affiliated Hospital of Xi'an Jiaotong University, Shaanxi 710061, China; Department of Laboratory Medicine, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi, 710061, China
| | - Zhihao Wang
- BioBank, The First Affiliated Hospital of Xi'an Jiaotong University, Shaanxi 710061, China; Institute for Protein Science and Phage Research, The First Affiliated Hospital of Xi'an Jiaotong University, Shaanxi 710061, China; MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London, UK
| | - Nancy Mulvenna
- MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London, UK
| | - Hang Yang
- Department of Pathogen Biology and Immunology, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi 710061, China
| | - Peipei Zhang
- BioBank, The First Affiliated Hospital of Xi'an Jiaotong University, Shaanxi 710061, China; Institute for Protein Science and Phage Research, The First Affiliated Hospital of Xi'an Jiaotong University, Shaanxi 710061, China
| | - Huan Chen
- BioBank, The First Affiliated Hospital of Xi'an Jiaotong University, Shaanxi 710061, China; Institute for Protein Science and Phage Research, The First Affiliated Hospital of Xi'an Jiaotong University, Shaanxi 710061, China
| | - Yan Li
- Department of Pathogen Biology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan, Hubei 430030, China
| | - Hongliang Wang
- Department of Pathogen Biology and Immunology, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi 710061, China
| | - Yongxiang Gao
- MOE Key Laboratory for Cellular Dynamics and School of Life Sciences, University of Science and Technology of China, Hefei 230027, China
| | | | - Steve Matthews
- Institute for Protein Science and Phage Research, The First Affiliated Hospital of Xi'an Jiaotong University, Shaanxi 710061, China; MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London, UK
| | - Kaiming Zhang
- MOE Key Laboratory for Cellular Dynamics and School of Life Sciences, University of Science and Technology of China, Hefei 230027, China.
| | - Bing Liu
- BioBank, The First Affiliated Hospital of Xi'an Jiaotong University, Shaanxi 710061, China; Institute for Protein Science and Phage Research, The First Affiliated Hospital of Xi'an Jiaotong University, Shaanxi 710061, China; Department of Laboratory Medicine, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi, 710061, China.
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9
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Jeong DE, Kim MS, Kim HR, Choi SK. Cell Factory Engineering of Undomesticated Bacillus Strains Using a Modified Integrative and Conjugative Element for Efficient Plasmid Delivery. Front Microbiol 2022; 13:802040. [PMID: 35558120 PMCID: PMC9086855 DOI: 10.3389/fmicb.2022.802040] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Accepted: 01/14/2022] [Indexed: 11/29/2022] Open
Abstract
A large number of Bacillus strains have been isolated from various environments and many of them have great potential as cell factories. However, they have been rarely developed as cell factories due to their poor transformation efficiency. In this study, we developed a highly efficient plasmid delivery system for undomesticated Bacillus strains using a modified integrative and conjugative element (MICE), which was designed to be activated by an inducer, prevent self-transfer, and deliver desired plasmids to the recipient cells. The MICE system was demonstrated to successfully introduce a gfp-containing plasmid into all 41 undomesticated Bacillus subtilis strains tested and eight other Bacillus species. The MICE was used to deliver a cytosine base editor (CBE)-based multiplex genome-editing tool for the cell factory engineering of the Bacillus species. The introduced CBE enabled one-step inactivation of the major extracellular protease genes of the tested strains. The engineered strains were used as hosts for heterologous expression of nattokinase, which resulted in various enzyme expression levels. The results suggested that the MICE and CBE systems can be powerful tools for genetic engineering of undomesticated Bacillus strains, and greatly contribute to the expansion of the Bacillus cell factory.
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Affiliation(s)
- Da-Eun Jeong
- Infectious Disease Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, South Korea
| | - Man Su Kim
- Infectious Disease Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, South Korea.,Department of Biosystems and Bioengineering, KRIBB School of Biotechnology, University of Science and Technology (UST), Daejeon, South Korea
| | - Ha-Rim Kim
- Infectious Disease Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, South Korea
| | - Soo-Keun Choi
- Infectious Disease Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, South Korea.,Department of Biosystems and Bioengineering, KRIBB School of Biotechnology, University of Science and Technology (UST), Daejeon, South Korea
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10
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Chromiková Z, Chovanová RK, Tamindžija D, Bártová B, Radnović D, Bernier-Latmani R, Barák I. Implantation of Bacillus pseudomycoides Chromate Transporter Increases Chromate Tolerance in Bacillus subtilis. Front Microbiol 2022; 13:842623. [PMID: 35330768 PMCID: PMC8940164 DOI: 10.3389/fmicb.2022.842623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Accepted: 02/14/2022] [Indexed: 11/23/2022] Open
Abstract
Chromium of anthropogenic origin contaminates the environment worldwide. The toxicity of chromium, a group I human carcinogen, is greatest when it is in a hexavalent oxidation state, Cr(VI). Cr(VI) is actively transported into the cell, triggering oxidative damage intracellularly. Due to the abundance of unspecific intracellular reductants, any microbial species is capable of bio-transformation of toxic Cr(VI) to innocuous Cr(III), however, this process is often lethal. Only some bacterial species are capable of sustaining the vegetative growth in the presence of a high concentration of Cr(VI) and thus operate as self-sustainable bioremediation agents. One of the successful microbial Cr(VI) detoxification strategies is the activation of chromate efflux pumps. This work describes transplantation of the chromate efflux pump from the potentially pathogenic but highly Cr resistant Bacillus pseudomycoides environmental strain into non-pathogenic but only transiently Cr tolerant Bacillus subtilis strain. In our study, we compared the two Bacillus spp. strains harboring evolutionarily diverged chromate efflux proteins. We have found that individual cells of the Cr-resistant B. pseudomycoides environmental strain accumulate less Cr than the cells of B. subtilis strain. Further, we found that survival of the B. subtilis strain during the Cr stress can be increased by the introduction of the chromate transporter from the Cr resistant environmental strain into its genome. Additionally, the expression of B. pseudomycoides chromate transporter ChrA in B. subtilis seems to be activated by the presence of chromate, hinting at versatility of Cr-efflux proteins. This study outlines the future direction for increasing the Cr-tolerance of non-pathogenic species and safe bioremediation using soil bacteria.
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Affiliation(s)
- Zuzana Chromiková
- Department of Microbial Genetics, Institute of Molecular Biology, Slovak Academy of Sciences, Bratislava, Slovakia
- *Correspondence: Zuzana Chromiková,
| | - Romana Kalianková Chovanová
- Department of Microbial Genetics, Institute of Molecular Biology, Slovak Academy of Sciences, Bratislava, Slovakia
| | - Dragana Tamindžija
- Department of Chemistry, Faculty of Sciences, Biochemistry and Environmental Protection, Novi Sad, Serbia
- Department of Biology and Ecology, Faculty of Sciences, University of Novi Sad, Novi Sad, Serbia
| | - Barbora Bártová
- Environmental Microbiology Laboratory, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Dragan Radnović
- Department of Biology and Ecology, Faculty of Sciences, University of Novi Sad, Novi Sad, Serbia
| | - Rizlan Bernier-Latmani
- Environmental Microbiology Laboratory, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Imrich Barák
- Department of Microbial Genetics, Institute of Molecular Biology, Slovak Academy of Sciences, Bratislava, Slovakia
- Imrich Barák,
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11
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Abstract
Understanding the underlying biology of pathogens is essential to develop novel treatment options. To drive this understanding, genetic tools are essential. In recent years, the genetic toolbox available to Clostridioides difficile researchers has expanded significantly but still requires the conjugal transfer of DNA from a donor strain into C. difficile. Here we describe an electroporation-based transformation protocol that was effective at introducing existing genetic tools into different C. difficile strains. An important risk factor for acquiring Clostridioides difficile infection is antibiotic use. Therefore, a detailed knowledge of the physiology and the virulence factors can help drive the development of new diagnostic tools and nonantibiotic therapeutic agents to combat these organisms. Several genetic systems are available to study C. difficile in the laboratory environment, and all rely on stably replicating or segregationally unstable plasmids. Currently, the transfer of plasmids into C. difficile can only be performed by conjugation using Escherichia coli or Bacillus subtilis as conjugal donors. Here we report a method to introduce plasmid DNA into C. difficile using electroporation and test factors that might contribute to higher transformation efficiencies: osmolyte used to stabilize weakened cells, DNA concentration, and recovery time postelectroporation. Depending on the C. difficile strain and plasmid used, this transformation protocol achieves between 20 and 200 colonies per microgram of DNA and is mostly influenced by the recovery time postelectroporation. Based on our findings, we recommend that each strain be tested for the optimum recovery time in each lab. IMPORTANCE Understanding the underlying biology of pathogens is essential to develop novel treatment options. To drive this understanding, genetic tools are essential. In recent years, the genetic toolbox available to Clostridioides difficile researchers has expanded significantly but still requires the conjugal transfer of DNA from a donor strain into C. difficile. Here we describe an electroporation-based transformation protocol that was effective at introducing existing genetic tools into different C. difficile strains.
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12
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Gheibi A, Khanahmad H, Kardar GA, Boshtam M, Rezaie S, Kazemi B, Khorramizadeh MR. Optimization and Comparison of Different Methods and Factors for Efficient Transformation of Brucella abortus RB51strain. Adv Biomed Res 2019; 8:37. [PMID: 31198771 PMCID: PMC6555225 DOI: 10.4103/abr.abr_14_19] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Background: The development of protective vaccines for Brucella spp. has been hampered by the difficulty in transformation of Brucella cells with foreign DNA for genetic manipulation. It seems that the formation of Brucella spheroplasts would increase the efficiency of transformation. The aim of this study was to devise an efficient method for the transformation of Brucella spp. Materials and Methods: At first, spheroplast of Brucella was prepared by glycine and ampicillin induction and transformed using optimized protocols of CaCl2, electroporation, and lipofection methods. Then, the efficacy of transformation was compared between the three-mentioned methods. Results: Ampicillin-induced spheroplasts from early-log phase culture of brucella when incubated in a medium-containing 0.2 M sucrose during cell recovery had higher transformation efficiency in three different methods. Comparison of the transformation efficiency of Brucella abortus RB51 using the CaCl2, lipofection, and electroporation methods revealed that the transformation efficiency with the lipofection method was significantly higher than with other two methods (P < 0.05). Conclusions: Lipofection method by lipofectamine 2000 on ampicillin-induced spheroplasts can be a suitable approach for Brucella transformation.
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Affiliation(s)
- Azam Gheibi
- Department of Medical Biotechnology, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Hossein Khanahmad
- Department of Genetics and Molecular Biology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Gholam Ali Kardar
- Department of Medical Biotechnology, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran.,Department of Immunology, Asthma and Allergy Research Institute, Children's Medical Center, Tehran University of Medical Sciences, Tehran, Iran
| | - Maryam Boshtam
- Isfahan Cardiovascular Research Center, Cardiovascular Research Institute, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Sassan Rezaie
- Department of Mycology and Parasitology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Bahram Kazemi
- Cellular and Molecular Biology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohammad Reza Khorramizadeh
- Biosensor Research Center, Endocrinology and Metabolism Molecular-Cellular Sciences Institute, Tehran University of Medical Sciences, Tehran, Iran
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13
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Yi Y, Li Z, Song C, Kuipers OP. Exploring plant-microbe interactions of the rhizobacteria Bacillus subtilis and Bacillus mycoides by use of the CRISPR-Cas9 system. Environ Microbiol 2018; 20:4245-4260. [PMID: 30051589 DOI: 10.1111/1462-2920.14305] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Revised: 05/31/2018] [Accepted: 06/04/2018] [Indexed: 01/12/2023]
Abstract
Bacillus subtilis HS3 and Bacillus mycoides EC18 are two rhizosphere-associated bacteria with plant growth-promoting activity. The CRISPR-Cas9 system was implemented to study various aspects of plant-microbe interaction mechanisms of these two environmental isolates. The results show that fengycin and surfactin are involved in the antifungal activity of B. subtilis HS3. Moreover, this strain emits several other volatile organic compounds than 2,3-butanediol, contributing to plant growth promotion. Confocal laser scanning microscopy observations of the GFP-labelled strain showed that HS3 selectively colonizes root hairs of grass (Lolium perenne) in a hydroponic system. For B. mycoides EC18, we found that the wild-type EC18 strain and a ΔasbA (petropectin-deficient) mutant, but not the ΔdhbB (bacillibactin-deficient) and ADKO (asbA and dhbB double knockout) mutants, can increase the plant biomass and total chlorophyll. All the mutant strains have a reduced colonization capability on Chinese cabbage (Brassica rapa) roots, at the root tip and root hair region compared with the wild-type strain. These results indicate that the siderophore, bacillibactin, is involved in the plant growth promoting activity and could affect the root colonization of B. mycoides. Collectively, the CRISPR-Cas9 system we developed for environmental isolates is broadly applicable and will facilitate deciphering the mechanisms of Bacillus-plant interactions. © 2018 The Authors.
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Affiliation(s)
- Yanglei Yi
- Molecular Genetics, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Groningen, The Netherlands
| | - Zhibo Li
- Molecular Genetics, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Groningen, The Netherlands
| | - Chunxu Song
- Molecular Genetics, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Groningen, The Netherlands
| | - Oscar P Kuipers
- Molecular Genetics, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Groningen, The Netherlands
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14
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Zhao X, Xu J, Tan M, Yu Z, Yang S, Zheng H, Song H. Construction of a plasmid interspecific transfer system in Bacillus species with the counter-selectable marker mazF. J Ind Microbiol Biotechnol 2018; 45:417-428. [PMID: 29737437 DOI: 10.1007/s10295-018-2038-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Accepted: 04/25/2018] [Indexed: 11/29/2022]
Abstract
Bacillus sp. strains as attractive hosts for the production of heterologous secretory proteins usually play important roles in bio-industry. However, low transformation efficiency of exogenous plasmids limited the application of Bacillus species. Here, a novel plasmid interspecific transfer system, with high transformation efficiency, high positive rate, and convenient manipulation, has been successfully constructed. A high electrotransformation efficiency strain Bacillus subtilis F-168 containing the counter-selectable marker mazF was used as the plasmid donor strain in this transfer method. A shuttled plasmid pBE980 and its recombinant plasmids pBE980::pulA and pBE980::HSPA were successfully transferred into the recipient Bacillus strains (Bacillus amyloliquefaciens 66, Bacillus licheniformis 124 and Bacillus megaterium 258) by this method. After co-culturing the donor cells (OD600nm = 1.3-1.7) and the recipient cells (OD600nm = 0.5-0.9) for 24 h in 22 °C, more than 1.0 × 105 positive transformants were obtained and a interspecific transformation efficiency of 1.0 × 10-3. It would provide a new approach for genetic manipulation in Bacillus strains and accelerate the research progress of the wild Bacillus strains in bio-industry.
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Affiliation(s)
- XingYa Zhao
- University of Chinese Academy of Sciences, Beijing, 100049, China.,Industrial Enzymes National Engineering Laboratory, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
| | - JianYong Xu
- Industrial Enzymes National Engineering Laboratory, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China.,Tianjin Key Laboratory for Industrial Biological, Systems and Bioprocessing Engineering, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
| | - Ming Tan
- Industrial Enzymes National Engineering Laboratory, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China.,Tianjin Key Laboratory for Industrial Biological, Systems and Bioprocessing Engineering, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
| | - ZhenXiao Yu
- University of Chinese Academy of Sciences, Beijing, 100049, China.,Industrial Enzymes National Engineering Laboratory, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
| | - ShiBin Yang
- University of Chinese Academy of Sciences, Beijing, 100049, China.,Industrial Enzymes National Engineering Laboratory, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
| | - HongChen Zheng
- Industrial Enzymes National Engineering Laboratory, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China. .,Tianjin Key Laboratory for Industrial Biological, Systems and Bioprocessing Engineering, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China.
| | - Hui Song
- University of Chinese Academy of Sciences, Beijing, 100049, China. .,Industrial Enzymes National Engineering Laboratory, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China. .,Tianjin Key Laboratory for Industrial Biological, Systems and Bioprocessing Engineering, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China.
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15
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Zhang Z, Ding Z, Zhong J, Zhou J, Shu D, Luo D, Yang J, Tan H. Improvement of iturin A production inBacillus subtilisZK0 by overexpression of thecomAandsigAgenes. Lett Appl Microbiol 2017; 64:452-458. [DOI: 10.1111/lam.12739] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Revised: 03/26/2017] [Accepted: 03/27/2017] [Indexed: 11/28/2022]
Affiliation(s)
- Z. Zhang
- Key Laboratory of Environmental and Applied Microbiology; Chengdu Institute of Biology; The Chinese Academy of Sciences; Chengdu China
- University of the Chinese Academy of Sciences; Beijing China
- Environmental Microbiology Key Laboratory of Sichuan Province; Chengdu Sichuan China
| | - Z.T. Ding
- Key Laboratory of Environmental and Applied Microbiology; Chengdu Institute of Biology; The Chinese Academy of Sciences; Chengdu China
- University of the Chinese Academy of Sciences; Beijing China
- Environmental Microbiology Key Laboratory of Sichuan Province; Chengdu Sichuan China
| | - J. Zhong
- Key Laboratory of Environmental and Applied Microbiology; Chengdu Institute of Biology; The Chinese Academy of Sciences; Chengdu China
- University of the Chinese Academy of Sciences; Beijing China
- Environmental Microbiology Key Laboratory of Sichuan Province; Chengdu Sichuan China
| | - J.Y. Zhou
- Key Laboratory of Environmental and Applied Microbiology; Chengdu Institute of Biology; The Chinese Academy of Sciences; Chengdu China
- Environmental Microbiology Key Laboratory of Sichuan Province; Chengdu Sichuan China
| | - D. Shu
- Key Laboratory of Environmental and Applied Microbiology; Chengdu Institute of Biology; The Chinese Academy of Sciences; Chengdu China
- Environmental Microbiology Key Laboratory of Sichuan Province; Chengdu Sichuan China
| | - D. Luo
- Key Laboratory of Environmental and Applied Microbiology; Chengdu Institute of Biology; The Chinese Academy of Sciences; Chengdu China
- Environmental Microbiology Key Laboratory of Sichuan Province; Chengdu Sichuan China
| | - J. Yang
- Key Laboratory of Environmental and Applied Microbiology; Chengdu Institute of Biology; The Chinese Academy of Sciences; Chengdu China
- Environmental Microbiology Key Laboratory of Sichuan Province; Chengdu Sichuan China
| | - H. Tan
- Key Laboratory of Environmental and Applied Microbiology; Chengdu Institute of Biology; The Chinese Academy of Sciences; Chengdu China
- University of the Chinese Academy of Sciences; Beijing China
- Environmental Microbiology Key Laboratory of Sichuan Province; Chengdu Sichuan China
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16
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Development of an efficient electroporation method for rhizobacterial Bacillus mycoides strains. J Microbiol Methods 2017; 133:82-86. [DOI: 10.1016/j.mimet.2016.12.022] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2016] [Revised: 12/23/2016] [Accepted: 12/23/2016] [Indexed: 11/22/2022]
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17
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How to transform a recalcitrant Paenibacillus strain: From culture medium to restriction barrier. J Microbiol Methods 2016; 131:135-143. [PMID: 27780731 DOI: 10.1016/j.mimet.2016.10.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Revised: 10/11/2016] [Accepted: 10/21/2016] [Indexed: 11/20/2022]
Abstract
Paenibacillus riograndensis SBR5T is a plant growth-promoting bacterium isolated from the wheat rhizosphere. Its recalcitrance to genetic manipulation is a major bottleneck for molecular studies, as has been reported for other Paenibacillus environmental isolates. An efficient electroporation protocol was established by evaluating diverse parameters and optimizing the culture medium, culture growth phase, electroporation solution, recovery medium, DNA input, and electric field strength. Efficiencies of approximately 2.8×104transformantsμg-1 of plasmid DNA were obtained. The optimized protocol was tested with other Paenibacillus species, and the relevance of bypassing the restriction DNA defense system to transform Paenibacillus was highlighted. This protocol is the tool needed to deepen molecular studies with this strain and will aid in the manipulation of other new environmental isolates that also exhibit recalcitrant transformation difficulties.
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