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Niu Z, Lei P, Wang Y, Wang J, Yang J, Zhang J. Small molecule LpxC inhibitors against gram-negative bacteria: Advances and future perspectives. Eur J Med Chem 2023; 253:115326. [PMID: 37023679 DOI: 10.1016/j.ejmech.2023.115326] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 03/18/2023] [Accepted: 03/28/2023] [Indexed: 04/03/2023]
Abstract
Uridine diphosphate-3-O-(hydroxymyristoyl)-N-acetylglucosamine deacetylase (LpxC) is a metalloenzyme with zinc ions as cofactors and is a key enzyme in the essential structural outer membrane lipid A synthesis commitment step of gram-negative bacteria. As LpxC is extremely homologous among different Gram-negative bacteria, it is conserved in almost all gram-negative bacteria, which makes LpxC a promising target. LpxC inhibitors have been reported extensively in recent years, such as PF-5081090 and CHIR-090 were found to have broad-spectrum antibiotic activity against P. aeruginosa and E. coli. They are mainly classified into hydroxamate inhibitors and non-hydroxamate inhibitors based on their structure, but no LpxC inhibitors have been marketed due to safety and activity issues. This review, therefore, focuses on small molecule inhibitors of LpxC against gram-negative pathogenic bacteria and covers recent advances in LpxC inhibitors, focusing on their structural optimization process, structure-activity relationships, and future directions, with the aim of providing ideas for the development of LpxC inhibitors and clinical research.
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Srichaiyapol O, Maddocks SE, Thammawithan S, Daduang S, Klaynongsruang S, Patramanon R. TA-AgNPs/Alginate Hydrogel and Its Potential Application as a Promising Antibiofilm Material against Polymicrobial Wound Biofilms Using a Unique Biofilm Flow Model. Microorganisms 2022; 10:2279. [PMID: 36422349 PMCID: PMC9692730 DOI: 10.3390/microorganisms10112279] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 11/09/2022] [Accepted: 11/12/2022] [Indexed: 07/30/2023] Open
Abstract
The presence of biofilm within a chronic wound may delay the healing process. Thus, control of biofilm formation and providing bactericidal effect are crucial factors for wound healing management. Alginate-based nanocomposite hydrogels have been suggested as dressing materials for wound treatment, which are employed as a biocompatible matrix. Therefore, in this study, we aimed to develop a biocompatible antimicrobial wound dressing containing AgNPs and demonstrate its efficacy against polymicrobial wound biofilms by using a biofilm flow device to simulate a chronic infected, exuding wound and specific wound environment. The results from agar well diffusion, the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) assays showed that TA-AgNPs exhibited antibacterial activity against wound pathogens. Additionally, the Minimum Biofilm Eradication Concentration assay (MBEC) demonstrated it could impair biofilm formation. Importantly, our TA-AgNPs/Alginate hydrogel clearly showed antibacterial activities against Streptococcus pyogenes, Staphylococcus aureus and Pseudomonas aeruginosa. Furthermore, we used the biofilm flow device to test the topical antimicrobial hydrogel against a three-species biofilm. We found that TA-AgNPs/Alginate hydrogel significantly showed a 3-4 log reduction in bacterial numbers when applied with multiple doses at 24 h intervals, and was especially effective against the chronic wound pathogen P. aeruginosa. This work highlighted that the TA-AgNPs/Alginate hydrogel is a promising material for treating complex wound biofilms.
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Affiliation(s)
- Oranee Srichaiyapol
- Department of Biochemistry, Faculty of Science, Khon Kaen University, Khon Kaen 40002, Thailand
| | - Sarah E. Maddocks
- Microbiology and Infection Research Group, Cardiff School of Health Sciences, Cardiff Metropolitan University, Cardiff CF5 2YB, UK
| | - Saengrawee Thammawithan
- Department of Biochemistry, Faculty of Science, Khon Kaen University, Khon Kaen 40002, Thailand
| | - Sakda Daduang
- Faculty of Pharmaceutical Sciences, Khon Kaen University, Khon Kaen 40002, Thailand
- Protein and Proteomics Research Center for Commercial and Industrial Purposes (ProCCI), Khon Kaen University, Khon Kaen 40002, Thailand
| | - Sompong Klaynongsruang
- Program Management Unit for Human Resources and Institutional Development, Research and Innovation (PMU-B), Bangkok 10330, Thailand
| | - Rina Patramanon
- Department of Biochemistry, Faculty of Science, Khon Kaen University, Khon Kaen 40002, Thailand
- Protein and Proteomics Research Center for Commercial and Industrial Purposes (ProCCI), Khon Kaen University, Khon Kaen 40002, Thailand
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3
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Engida HA, Theuri DM, Gathungu D, Gachohi J, Alemneh HT. A mathematical model analysis of the human melioidosis transmission dynamics with an asymptomatic case. Heliyon 2022; 8:e11720. [PMID: 36411894 PMCID: PMC9674546 DOI: 10.1016/j.heliyon.2022.e11720] [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: 03/21/2022] [Revised: 05/26/2022] [Accepted: 11/11/2022] [Indexed: 11/17/2022] Open
Abstract
In this paper, we develop and examine a mathematical model of human melioidosis transmission with asymptomatic cases to describe the dynamics of the epidemic. The basic reproduction number ( R 0 ) of the model is obtained. Disease-free equilibrium of the model is proven to be globally asymptotically stable whenR 0 is less than the unity, while the endemic equilibrium of the model is shown to be locally asymptotically stable ifR 0 is greater than unity. Sensitivity analysis is performed to illustrate the effect of the model parameters influencing on the disease dynamics. Furthermore, numerical experiments of the model are conducted to validate the theoretical findings.
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Affiliation(s)
- Habtamu Ayalew Engida
- Pan African University for Basic Science, Technology and Invocation (PAUSTI)/JKUAT, Nairobi, Kenya
| | - David Mwangi Theuri
- Department of Mathematics, Jomo Kenyatta University of Agriculture and Technology, Nairobi, Kenya
| | - Duncan Gathungu
- Department of Mathematics, Jomo Kenyatta University of Agriculture and Technology, Nairobi, Kenya
| | - John Gachohi
- School of Public Health, Jomo Kenyatta University of Agriculture and Technology, Nairobi, Kenya
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Thonglao N, Pakkulnan R, Paluka J, Chareonsudjai P, Kanokmedhakul S, Kanokmedhakul K, Chareonsudjai S. Chitosan biological molecule improves bactericidal competence of ceftazidime against Burkholderia pseudomallei biofilms. Int J Biol Macromol 2022; 201:676-685. [PMID: 35063492 DOI: 10.1016/j.ijbiomac.2022.01.053] [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: 05/25/2021] [Revised: 01/06/2022] [Accepted: 01/09/2022] [Indexed: 11/05/2022]
Abstract
Biofilm-associated Burkholderia pseudomallei infections (melioidosis) are problematic because of reduced sensitivity to antibiotics and high frequency of relapse. Biofilm dispersal agents are essential to liberate the biofilm-encased cells, which then become planktonic and are more susceptible to antibiotics. This study aimed to evaluate the ability of deacetylated chitosan (dCS), an antimicrobial and antibiofilm biological macromolecule, to disrupt established biofilms, thus enabling ceftazidime (CAZ) to kill biofilm-embedded B. pseudomallei. We combined dCS with CAZ using a mechanical stirring method to generate dCS/CAZ. In combination, 1.25-2.5 mg ml-1 dCS/1-2 μg ml-1 CAZ acted synergistically to kill cells more effectively than did either dCS or CAZ alone. Notably, a combination of 5-10 mg ml-1 dCS with 256-512 μg ml-1 CAZ, prepared either by mechanical stirring (dCS/CAZ) or mixing (dCS + CAZ), drastically improved bactericidal activities against biofilm cells leading to a 3-6 log CFU reduction. Confocal laser-scanning microscope (CLSM) images revealed that 10 mg ml-1 dCS/512 μg ml-1 CAZ is by far the best formulation to diminish B. pseudomallei biofilm biomass and produces the lowest live/dead cell ratios of B. pseudomallei in biofilm matrix. Collectively, these findings emphasize the potential of novel therapeutic antibacterial and antibiofilm agents to fight against antibiotic-tolerant B. pseudomallei biofilm-associated infections.
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Affiliation(s)
- Nuttaya Thonglao
- Department of Microbiology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
| | - Rattiyaphorn Pakkulnan
- Department of Microbiology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
| | - Jakkapat Paluka
- Natural Product Research Unit, Center of Excellence for Innovation in Chemistry, Department of Chemistry, Faculty of Science, Khon Kaen University, Khon Kaen, Thailand
| | - Pisit Chareonsudjai
- Department of Environmental Science, Faculty of Science, Khon Kaen University, Khon Kaen, Thailand; Biofilm Research Group, Khon Kaen University, Khon Kaen, Thailand
| | - Somdej Kanokmedhakul
- Natural Product Research Unit, Center of Excellence for Innovation in Chemistry, Department of Chemistry, Faculty of Science, Khon Kaen University, Khon Kaen, Thailand
| | - Kwanjai Kanokmedhakul
- Natural Product Research Unit, Center of Excellence for Innovation in Chemistry, Department of Chemistry, Faculty of Science, Khon Kaen University, Khon Kaen, Thailand
| | - Sorujsiri Chareonsudjai
- Department of Microbiology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand; Biofilm Research Group, Khon Kaen University, Khon Kaen, Thailand; Research and Diagnostic Center for Emerging Infectious Diseases (RCEID), Khon Kaen, Thailand.
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5
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Gunardi WD, Timotius KH, Natasha A, Evriarti PR. Biofilm Targeting Strategy in the Eradication of Burkholderia Infections: A Mini-Review. Open Microbiol J 2021. [DOI: 10.2174/1874285802115010051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Burkholderia are intracellular pathogenic bacteria which can produce biofilm. This biofilm protects the intracellular pathogenic bacteria from antibiotic treatment and the immunological system of the host. Therefore, this review aims to describe the capacity of Burkholderia to form a biofilm, the regulation of its biofilm formation, the efficacy of antibiotics to eradicate biofilm, and the novel therapy which targets its biofilm. Burkholderia's biofilm is characterized by its lipopolysaccharides, exopolysaccharides (EPSs), biofilm-associated proteins, and eDNA. Its regulation is made by quorum sensing, c-di-AMP, sRNA, and two component systems. Many antibiotics have been used as sole or mixture agents; however, they are not always effective in eradicating the biofilm-forming Burkholderia. Inhibitors of quorum sensing and other non-conventional antibiotic approaches are promising to discover effective treatment of Burkholderia infections.
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Srichaiyapol O, Thammawithan S, Siritongsuk P, Nasompag S, Daduang S, Klaynongsruang S, Kulchat S, Patramanon R. Tannic Acid-Stabilized Silver Nanoparticles Used in Biomedical Application as an Effective Antimelioidosis and Prolonged Efflux Pump Inhibitor against Melioidosis Causative Pathogen. Molecules 2021; 26:1004. [PMID: 33672903 PMCID: PMC7918740 DOI: 10.3390/molecules26041004] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 02/03/2021] [Accepted: 02/11/2021] [Indexed: 11/17/2022] Open
Abstract
Burkholderia pseudomallei is the causative pathogen of melioidosis and this bacterium is resistant to several antibiotics. Silver nanoparticles (AgNPs) are an interesting agent to develop to solve this bacterial resistance. Here, we characterize and assess the antimelioidosis activity of AgNPs against these pathogenic bacteria. AgNPs were characterized and displayed a maximum absorption band at 420 nm with a spherical shape, being well-monodispersed and having high stability in solution. The average size of AgNPs is 7.99 ± 1.46 nm. The antibacterial efficacy of AgNPs was evaluated by broth microdilution. The bactericidal effect of AgNPs was further assessed by time-kill kinetics assay. Moreover, the effect of AgNPs on the inhibition of the established biofilm was investigated by the crystal violet method. In parallel, a study of the resistance induction development of B. pseudomallei towards AgNPs with efflux pump inhibiting effect was performed. We first found that AgNPs had strong antibacterial activity against both susceptible and ceftazidime-resistant (CAZ-resistant) strains, as well as being efficiently active against B. pseudomallei CAZ-resistant strains with a fast-killing mode via a bactericidal effect within 30 min. These AgNPs did not only kill planktonic bacteria in broth conditions, but also in established biofilm. Our findings first documented that the resistance development was not induced in B. pseudomallei toward AgNPs in the 30th passage. We found that AgNPs still showed an effective efflux pump inhibiting effect against these bacteria after prolonged exposure to AgNPs at sublethal concentrations. Thus, AgNPs have valuable properties for being a potent antimicrobial agent to solve the antibiotic resistance problem in pathogens.
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Affiliation(s)
- Oranee Srichaiyapol
- Department of Biochemistry, Faculty of Science, Khon Kaen University, Khon Kaen 40002, Thailand; (O.S.); (S.T.); (P.S.); (S.K.)
| | - Saengrawee Thammawithan
- Department of Biochemistry, Faculty of Science, Khon Kaen University, Khon Kaen 40002, Thailand; (O.S.); (S.T.); (P.S.); (S.K.)
| | - Pawinee Siritongsuk
- Department of Biochemistry, Faculty of Science, Khon Kaen University, Khon Kaen 40002, Thailand; (O.S.); (S.T.); (P.S.); (S.K.)
| | - Sawinee Nasompag
- Research Instrument Center, Khon Kaen University, Khon Kaen 40002, Thailand;
- Interdisciplinary Graduate Program in Genetic Engineering, Graduate School, Kasetsart University, Bangkok 10900, Thailand
| | - Sakda Daduang
- Protein and Proteomics Research Center for Commercial and Industrial Purposes (ProCCI), Khon Kaen University, Khon Kaen 40002, Thailand;
- Faculty of Pharmaceutical Sciences, Khon Kaen University, Khon Kaen 40002, Thailand
| | - Sompong Klaynongsruang
- Department of Biochemistry, Faculty of Science, Khon Kaen University, Khon Kaen 40002, Thailand; (O.S.); (S.T.); (P.S.); (S.K.)
- Protein and Proteomics Research Center for Commercial and Industrial Purposes (ProCCI), Khon Kaen University, Khon Kaen 40002, Thailand;
| | - Sirinan Kulchat
- Department of Chemistry, Faculty of Science, Khon Kaen University, Khon Kaen 40002, Thailand;
| | - Rina Patramanon
- Department of Biochemistry, Faculty of Science, Khon Kaen University, Khon Kaen 40002, Thailand; (O.S.); (S.T.); (P.S.); (S.K.)
- Protein and Proteomics Research Center for Commercial and Industrial Purposes (ProCCI), Khon Kaen University, Khon Kaen 40002, Thailand;
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Shi L, Chen J, Yi G. Burkholderia pseudomallei was Identified in a Melioidosis Aneurysm using Polymerase Chain Reaction Targeting 23S rRNA. Ann Vasc Surg 2020; 68:569.e13-569.e20. [PMID: 32339680 DOI: 10.1016/j.avsg.2020.04.035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Revised: 03/28/2020] [Accepted: 04/04/2020] [Indexed: 10/24/2022]
Abstract
Melioidosis abdominal aortic aneurysm and splenic abscesses lead to poor prognosis and high mortality rate as high as 50% due to delayed/missed diagnosis. We describe an attempt to identify Burkholderia pseudomallei immediately, which was confirmed by polymerase chain reaction (PCR) and gene sequence analysis of 23S rRNA gene. PCR is not only an unambiguous identification of B. pseudomallei but also a rapid detection because B. pseudomallei may not be readily isolated. For patients of melioidosis abdominal aortic aneurysm with spleen abscess, prolonged antibiotic therapy, splenectomy and artificial vessel replacement provided an excellent result in our study. The progression, roentgenographic findings and histopathology character of melioidosis are similar to those of tuberculosis disease. PCR is useful to differentiate B. pseudomallei from Mycobacterium tuberculosis.
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Affiliation(s)
- Li Shi
- The Infective Disease Department and Tropical Medicine Research Unit, Affiliated Hainan Hospital of Hainan Medical University, Haikou, Hainan Province, People's Republic of China.
| | - Jie Chen
- Acupuncture and Massage Institute, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong Province, People's Republic of China
| | - Gao Yi
- The Infective Disease Department and Tropical Medicine Research Unit, Affiliated Hainan Hospital of Hainan Medical University, Haikou, Hainan Province, People's Republic of China
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Abstract
The causative agent of melioidosis, Burkholderia pseudomallei, a tier 1 select agent, is endemic in Southeast Asia and northern Australia, with increased incidence associated with high levels of rainfall. Increasing reports of this condition have occurred worldwide, with estimates of up to 165,000 cases and 89,000 deaths per year. The ecological niche of the organism has yet to be clearly defined, although the organism is associated with soil and water. The culture of appropriate clinical material remains the mainstay of laboratory diagnosis. Identification is best done by phenotypic methods, although mass spectrometric methods have been described. Serology has a limited diagnostic role. Direct molecular and antigen detection methods have limited availability and sensitivity. Clinical presentations of melioidosis range from acute bacteremic pneumonia to disseminated visceral abscesses and localized infections. Transmission is by direct inoculation, inhalation, or ingestion. Risk factors for melioidosis include male sex, diabetes mellitus, alcohol abuse, and immunosuppression. The organism is well adapted to intracellular survival, with numerous virulence mechanisms. Immunity likely requires innate and adaptive responses. The principles of management of this condition are drainage and debridement of infected material and appropriate antimicrobial therapy. Global mortality rates vary between 9% and 70%. Research into vaccine development is ongoing.
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Affiliation(s)
- I Gassiep
- Pathology Queensland, Townsville Hospital, Townsville, Queensland, Australia
- Faculty of Medicine, University of Queensland, Brisbane, Queensland, Australia
| | - M Armstrong
- Pathology Queensland, Townsville Hospital, Townsville, Queensland, Australia
| | - R Norton
- Pathology Queensland, Townsville Hospital, Townsville, Queensland, Australia
- Faculty of Medicine, University of Queensland, Brisbane, Queensland, Australia
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Tapia D, Sanchez-Villamil JI, Torres AG. Emerging role of biologics for the treatment of melioidosis and glanders. Expert Opin Biol Ther 2019; 19:1319-1332. [PMID: 31590578 PMCID: PMC6981286 DOI: 10.1080/14712598.2019.1677602] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Accepted: 10/03/2019] [Indexed: 12/15/2022]
Abstract
Introduction: Two important pathogenic species within the genus Burkholderia, namely Burkholderia pseudomallei (Bpm) and Burkholderia mallei (Bm), are the causative agents of the life-threatening diseases melioidosis and glanders, respectively. Due to their high mortality rate and potential for aerosolization, they have gained interest as potential biothreat agents and are classified as Tier 1 Select Agents.Areas covered: The manuscript provides an overview of the literature covering the efforts taken in the last 10 years to develop new therapeutics measures against both Bpm and Bm, with attention on novel therapeutic agents.Expert Opinion: As a result of the complicated antibiotic regimens necessary to treat these infections, development of novel therapeutics is needed to treat both diseases. In recent years, the understanding of the pathogenesis of Burkholderia has improved significantly and so have the efforts to develop novel therapeutic agents with high efficacy, either alone, or in combination with conventional antibiotics.
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Affiliation(s)
- Daniel Tapia
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Javier I. Sanchez-Villamil
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Alfredo G. Torres
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, Texas, United States of America
- Department of Pathology, University of Texas Medical Branch, Galveston, Texas, United States of America
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Sharma A, Kumar V, Pratap S, Kumar P. The inhibitory and binding studies of methyl-sulfone hydroxamate based inhibitors against LpxC from drug resistant Moraxella catarrhalis using biophysical, biochemical and in silico approaches. Int J Biol Macromol 2018; 118:1747-1762. [DOI: 10.1016/j.ijbiomac.2018.07.025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Revised: 07/06/2018] [Accepted: 07/07/2018] [Indexed: 01/17/2023]
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Richie DL, Wang L, Chan H, De Pascale G, Six DA, Wei JR, Dean CR. A pathway-directed positive growth restoration assay to facilitate the discovery of lipid A and fatty acid biosynthesis inhibitors in Acinetobacter baumannii. PLoS One 2018; 13:e0193851. [PMID: 29505586 PMCID: PMC5837183 DOI: 10.1371/journal.pone.0193851] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2017] [Accepted: 02/19/2018] [Indexed: 11/19/2022] Open
Abstract
Acinetobacter baumannii ATCC 19606 can grow without lipooligosaccharide (LOS). Lack of LOS can result from disruption of the early lipid A biosynthetic pathway genes lpxA, lpxC or lpxD. Although LOS itself is not essential for growth of A. baumannii ATCC 19606, it was previously shown that depletion of the lipid A biosynthetic enzyme LpxK in cells inhibited growth due to the toxic accumulation of lipid A pathway intermediates. Growth of LpxK-depleted cells was restored by chemical inhibition of LOS biosynthesis using CHIR-090 (LpxC) and fatty acid biosynthesis using cerulenin (FabB/F) and pyridopyrimidine (acetyl-CoA-carboxylase). Here, we expand on this by showing that inhibition of enoyl-acyl carrier protein reductase (FabI), responsible for converting trans-2-enoyl-ACP into acyl-ACP during the fatty acid elongation cycle also restored growth during LpxK depletion. Inhibition of fatty acid biosynthesis during LpxK depletion rescued growth at 37°C, but not at 30°C, whereas rescue by LpxC inhibition was temperature independent. We exploited these observations to demonstrate proof of concept for a targeted medium-throughput growth restoration screening assay to identify small molecule inhibitors of LOS and fatty acid biosynthesis. The differential temperature dependence of fatty acid and LpxC inhibition provides a simple means by which to separate growth stimulating compounds by pathway. Targeted cell-based screening platforms such as this are important for faster identification of compounds inhibiting pathways of interest in antibacterial discovery for clinically relevant Gram-negative pathogens.
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Affiliation(s)
- Daryl L. Richie
- Novartis Institutes for BioMedical Research, Emeryville, CA, United States of America
| | - Lisha Wang
- Novartis Institutes for BioMedical Research, Emeryville, CA, United States of America
| | - Helen Chan
- Novartis Institutes for BioMedical Research, Emeryville, CA, United States of America
| | - Gianfranco De Pascale
- Novartis Institutes for BioMedical Research, Emeryville, CA, United States of America
| | - David A. Six
- Novartis Institutes for BioMedical Research, Emeryville, CA, United States of America
| | - Jun-Rong Wei
- Novartis Institutes for BioMedical Research, Emeryville, CA, United States of America
| | - Charles R. Dean
- Novartis Institutes for BioMedical Research, Emeryville, CA, United States of America
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Sengyee S, Yoon SH, Paksanont S, Yimthin T, Wuthiekanun V, Limmathurotsakul D, West TE, Ernst RK, Chantratita N. Comprehensive analysis of clinical Burkholderia pseudomallei isolates demonstrates conservation of unique lipid A structure and TLR4-dependent innate immune activation. PLoS Negl Trop Dis 2018; 12:e0006287. [PMID: 29474381 PMCID: PMC5842036 DOI: 10.1371/journal.pntd.0006287] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Revised: 03/07/2018] [Accepted: 01/31/2018] [Indexed: 11/18/2022] Open
Abstract
Burkholderia pseudomallei is an environmental bacterium that causes melioidosis, a major community-acquired infection in tropical regions. Melioidosis presents with a range of clinical symptoms, is often characterized by a robust inflammatory response, may relapse after treatment, and results in high mortality rates. Lipopolysaccharide (LPS) of B. pseudomallei is a potent immunostimulatory molecule comprised of lipid A, core, and O-polysaccharide (OPS) components. Four B. pseudomallei LPS types have been described based on SDS-PAGE patterns that represent the difference of OPS-type A, type B, type B2 and rough LPS. The majority of B. pseudomallei isolates are type A. We used matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) followed by electrospray ionization quadrupole time-of-flight mass spectrometry (ESI-QqTOF MS) and gas chromatography to characterize the lipid A of B. pseudomallei within LPS type A isolates. We determined that B. pseudomallei lipid A is represented by penta- and tetra-acylated species modified with 4-amino-4-deoxy-arabinose (Ara4N). The MALDI-TOF profiles from 171 clinical B. pseudomallei isolates, including 68 paired primary and relapse isolates and 35 within-host isolates were similar. We did not observe lipid A structural changes when the bacteria were cultured in different growth conditions. Dose-dependent NF-κB activation in HEK cells expressing TLR4 was observed using multiple heat-killed B. pseudomallei isolates and corresponding purified LPS. We demonstrated that TLR4-dependent NF-κB activation induced by heat-killed bacteria or LPS prepared from OPS deficient mutant was significantly greater than those induced by wild type B. pseudomallei. These findings suggest that the structure of B. pseudomallei lipid A is highly conserved in a wide variety of clinical and environmental circumstances but that the presence of OPS may modulate LPS-driven innate immune responses in melioidosis.
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Affiliation(s)
- Sineenart Sengyee
- Department of Microbiology and Immunology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Sung Hwan Yoon
- Department of Microbial Pathogenesis, University of Maryland, Baltimore, MD, United States of America
| | - Suporn Paksanont
- Department of Microbiology and Immunology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Thatcha Yimthin
- Department of Microbiology and Immunology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Vanaporn Wuthiekanun
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Direk Limmathurotsakul
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
- Department of Tropical Hygiene, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - T. Eoin West
- Division of Pulmonary and Critical Care Medicine, Harborview Medical Center, University of Washington, Seattle, WA, United States of America
- International Respiratory and Severe Illness Center, University of Washington, Seattle, WA, United States of America
| | - Robert K. Ernst
- Department of Microbial Pathogenesis, University of Maryland, Baltimore, MD, United States of America
| | - Narisara Chantratita
- Department of Microbiology and Immunology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
- * E-mail:
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