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McMillan IA, Norris MH, Heacock-Kang Y, Zarzycki-Siek J, Sun Z, Hartney BA, Filipowska LK, Islam MN, Crick DC, Borlee BR, Hoang TT. TetR-like regulator BP1026B_II1561 controls aromatic amino acid biosynthesis and intracellular pathogenesis in Burkholderia pseudomallei. Front Microbiol 2024; 15:1441330. [PMID: 39211319 PMCID: PMC11358695 DOI: 10.3389/fmicb.2024.1441330] [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: 05/30/2024] [Accepted: 07/29/2024] [Indexed: 09/04/2024] Open
Abstract
Burkholderia pseudomallei (Bp) causes the tropical disease melioidosis that afflicts an estimated 165,000 people each year. Bp is a facultative intracellular pathogen that transits through distinct intracellular stages including attachment to host cells, invasion through the endocytic pathway, escape from the endosome, replication in the cytoplasm, generation of protrusions towards neighboring cells, and host cell fusion allowing Bp infection to spread without exiting the intracellular environment. We have identified a TetR-like transcriptional regulator, BP1026B_II1561, that is up-regulated during the late stages of infection as Bp protrudes toward neighboring cells. We have characterized BP1026B_II1561 and determined that it has a role in pathogenesis. A deletional mutant of BP1026B_II1561 is attenuated in RAW264.7 macrophage and BALB/c mouse models of infection. Using RNA-seq, we found that BP1026B_II1561 controls secondary metabolite biosynthesis, fatty acid degradation, and propanoate metabolism. In addition, we identified that BP1026B_II1561 directly controls expression of an outer membrane porin and genes in the shikimate biosynthetic pathway using ChIP-seq. Transposon mutants of genes within the BP1026B_II1561 regulon show defects during intracellular replication in RAW264.7 cells confirming the role of this transcriptional regulator and the pathways it controls in pathogenesis. BP1026B_II1561 also up-regulates the majority of the enzymes in shikimate and tryptophan biosynthetic pathways, suggesting their importance for Bp physiology. To investigate this, we tested fluorinated analogs of anthranilate and tryptophan, intermediates and products of the shikimate and tryptophan biosynthetic pathways, respectively, and showed inhibition of Bp growth at nanomolar concentrations. The expression of these pathways by BP1026b_II1561 and during intracellular infection combined with the inhibition of Bp growth by fluorotryptophan/anthranilate highlights these pathways as potential targets for therapeutic intervention against melioidosis. In the present study, we have identified BP1026B_II1561 as a critical transcriptional regulator for Bp pathogenesis and partially characterized its role during host cell infection.
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Affiliation(s)
- Ian A. McMillan
- School of Life Sciences, University of Hawaiʻi at Mānoa, Honolulu, HI, United States
| | - Michael H. Norris
- Pathogen Analysis and Translational Health Group, School of Life Sciences, University of Hawaiʻi at Mānoa, Honolulu, HI, United States
| | - Yun Heacock-Kang
- School of Life Sciences, University of Hawaiʻi at Mānoa, Honolulu, HI, United States
| | - Jan Zarzycki-Siek
- School of Life Sciences, University of Hawaiʻi at Mānoa, Honolulu, HI, United States
| | - Zhenxin Sun
- School of Life Sciences, University of Hawaiʻi at Mānoa, Honolulu, HI, United States
| | - Brooke A. Hartney
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, United States
| | - Liliana K. Filipowska
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, United States
| | - M. Nurul Islam
- Department of Chemistry, Biochemistry, and Physics, South Dakota State University, Brookings, SD, United States
| | - Dean C. Crick
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, United States
| | - Bradley R. Borlee
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, United States
| | - Tung T. Hoang
- School of Life Sciences, University of Hawaiʻi at Mānoa, Honolulu, HI, United States
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Sun Z, Heacock-Kang Y, McMillan IA, Cabanas D, Zarzycki-Siek J, Hoang TT. A virulence activator of a surface attachment protein in Burkholderia pseudomallei acts as a global regulator of other membrane-associated virulence factors. Front Microbiol 2023; 13:1063287. [PMID: 36726566 PMCID: PMC9884982 DOI: 10.3389/fmicb.2022.1063287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Accepted: 12/30/2022] [Indexed: 01/19/2023] Open
Abstract
Burkholderia pseudomallei (Bp), causing a highly fatal disease called melioidosis, is a facultative intracellular pathogen that attaches and invades a variety of cell types. We previously identified BP1026B_I0091 as a surface attachment protein (Sap1) and an essential virulence factor, contributing to Bp pathogenesis in vitro and in vivo. The expression of sap1 is regulated at different stages of Bp intracellular lifecycle by unidentified regulator(s). Here, we identified SapR (BP1026B_II1046) as a transcriptional regulator that activates sap1, using a high-throughput transposon mutagenesis screen in combination with Tn-Seq. Consistent with phenotypes of the Δsap1 mutant, the ΔsapR activator mutant exhibited a significant reduction in Bp attachment to the host cell, leading to subsequent decreased intracellular replication. RNA-Seq analysis further revealed that SapR regulates sap1. The regulation of sap1 by SapR was confirmed quantitatively by qRT-PCR, which also validated the RNA-Seq data. SapR globally regulates genes associated with the bacterial membrane in response to diverse environments, and some of the genes regulated by SapR are virulence factors that are required for Bp intracellular infection (e.g., type III and type VI secretion systems). This study has identified the complex SapR regulatory network and its importance as an activator of an essential Sap1 attachment factor.
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Affiliation(s)
- Zhenxin Sun
- School of Life Sciences, University of Hawai'i at Mānoa, Honolulu, HI, United States
| | - Yun Heacock-Kang
- School of Life Sciences, University of Hawai'i at Mānoa, Honolulu, HI, United States
| | - Ian A McMillan
- School of Life Sciences, University of Hawai'i at Mānoa, Honolulu, HI, United States
| | - Darlene Cabanas
- School of Life Sciences, University of Hawai'i at Mānoa, Honolulu, HI, United States
| | - Jan Zarzycki-Siek
- School of Life Sciences, University of Hawai'i at Mānoa, Honolulu, HI, United States
| | - Tung T Hoang
- School of Life Sciences, University of Hawai'i at Mānoa, Honolulu, HI, United States
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Transcriptional Potential Determines the Adaptability of Escherichia coli Strains with Different Fitness Backgrounds. Microbiol Spectr 2022; 10:e0252822. [PMID: 36445144 PMCID: PMC9769844 DOI: 10.1128/spectrum.02528-22] [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] [Indexed: 12/03/2022] Open
Abstract
Adaptation through the fitness landscape may be influenced by the gene pool or expression network. However, genetic factors that determine the contribution of beneficial mutations during adaptive evolution are poorly understood. In this study, we experimentally evolved wild-type Escherichia coli K-12 MG1655 and its isogenic derivative that has two additional replication origins and shows higher background fitness. During the short time of experimental evolution, the fitness gains of the two E. coli strains with different fitness backgrounds converged. Populational genome sequencing revealed various mutations with different allele frequencies in evolved populations. Several mutations occurred in genes affecting transcriptional regulation (e.g., RNA polymerase subunit, RNase, ppGpp synthetase, and transcription termination/antitermination factor genes). When we introduced mutations into the ancestral E. coli strains, beneficial effects tended to be lower in the ancestor with higher initial fitness. Replication rate analysis showed that the various replication indices do not correlate with the growth rate. Transcriptome profiling showed that gene expression and gene ontology are markedly enriched in populations with lower background fitness after experimental evolution. Further, the degree of transcriptional change was proportional to the fitness gain. Thus, the evolutionary trajectories of bacteria with different fitness backgrounds can be complex and counterintuitive. Notably, transcriptional change is a major contributor to adaptability. IMPORTANCE Predicting the adaptive potential of bacterial populations can be difficult due to their complexity and dynamic environmental conditions. Also, epistatic interaction between mutations affects the adaptive trajectory. Nevertheless, next-generation sequencing sheds light on understanding evolutionary dynamics through high-throughput genome and transcriptome information. Experimental evolution of two E. coli strains with different background fitness showed that the trajectories of fitness gain, which slowed down during the later stages of evolution, became convergent. This suggests that the adaptability of bacteria can be counterintuitive and that predicting the evolutionary path of bacteria can be difficult even in a constant environment. In addition, transcriptional change is associated with fitness gain during the evolutionary process. Thus, the adaptability of cells depends on their intrinsic genetic capacity for a given evolutionary period. This should be considered when genetically engineered bacteria are optimized through adaptive evolution.
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Liu K, Abouelhassan Y, Zhang Y, Jin S, Huigens Iii RW. Transcript Profiling of Nitroxoline-Treated Biofilms Shows Rapid Up-regulation of Iron Acquisition Gene Clusters. ACS Infect Dis 2022; 8:1594-1605. [PMID: 35830188 PMCID: PMC10549994 DOI: 10.1021/acsinfecdis.2c00206] [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] [Indexed: 11/30/2022]
Abstract
Bacterial biofilms are surface-attached communities of slow- or non-replicating cells embedded within a protective matrix of biomolecules. Unlike free-floating planktonic bacteria, biofilms are innately tolerant to conventional antibiotics and are prevalent in recurring and chronic infections. Nitroxoline, a broad-spectrum biofilm-eradicating agent, was used to probe biofilm viability. Transcript profiling (RNA-seq) showed that 452 of 2594 genes (17.4%) in methicillin-resistant Staphylococcus aureus (MRSA) biofilms were differentially expressed after a 2 h treatment of nitroxoline. WoPPER analysis and time-course validation (RT-qPCR) revealed that gene clusters involved in iron acquisition (sbn, isd, MW2101, MW0695, fhu, and feo) were rapidly up-regulated following nitroxoline treatment, which is indicative of iron starvation in MRSA biofilms. In addition, genes related to oligopeptide transporters and riboflavin biosynthesis were found to be up-regulated, while genes related to carotenoid biosynthesis and nitrate assimilation were down-regulated. RT-qPCR experiments revealed that iron uptake transcripts were also up-regulated in established Staphylococcus epidermidis and Acinetobacter baumannii biofilms following nitroxoline treatment. Overall, we show RNA-seq to be an ideal platform to define cellular pathways critical for biofilm survival, in addition to demonstrating the need these bacterial communities have for iron.
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Affiliation(s)
- Ke Liu
- Department of Medicinal Chemistry, Center for Natural Products, Drug Discovery and Development (CNPD3), College of Pharmacy, University of Florida, Gainesville, Florida 32610, United States
| | - Yasmeen Abouelhassan
- Department of Medicinal Chemistry, Center for Natural Products, Drug Discovery and Development (CNPD3), College of Pharmacy, University of Florida, Gainesville, Florida 32610, United States
| | - Yanping Zhang
- Interdisciplinary Center for Biotechnology Research (ICBR), Gene Expression and Genotyping, University of Florida, Gainesville, Florida 32610, United States
| | - Shouguang Jin
- Department of Molecular Genetics & Microbiology, College of Medicine, University of Florida, Gainesville, Florida 32610, United States
| | - Robert W Huigens Iii
- Department of Medicinal Chemistry, Center for Natural Products, Drug Discovery and Development (CNPD3), College of Pharmacy, University of Florida, Gainesville, Florida 32610, United States
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Borlee GI, Mangalea MR, Martin KH, Plumley BA, Golon SJ, Borlee BR. Disruption of c-di-GMP Signaling Networks Unlocks Cryptic Expression of Secondary Metabolites during Biofilm Growth in Burkholderia pseudomallei. Appl Environ Microbiol 2022; 88:e0243121. [PMID: 35357191 PMCID: PMC9040570 DOI: 10.1128/aem.02431-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Accepted: 03/04/2022] [Indexed: 11/20/2022] Open
Abstract
The regulation and production of secondary metabolites during biofilm growth of Burkholderia spp. is not well understood. To learn more about the crucial role and regulatory control of cryptic molecules produced during biofilm growth, we disrupted c-di-GMP signaling in Burkholderia pseudomallei, a soilborne bacterial saprophyte and the etiologic agent of melioidosis. Our approach to these studies combined transcriptional profiling with genetic deletions that targeted key c-di-GMP regulatory components to characterize responses to changes in temperature. Mutational analyses and conditional expression studies of c-di-GMP genes demonstrates their contribution to phenotypes such as biofilm formation, colony morphology, motility, and expression of secondary metabolite biosynthesis when grown as a biofilm at different temperatures. RNA-seq analysis was performed at various temperatures in a ΔII2523 mutant background that is responsive to temperature alterations resulting in hypobiofilm- and hyperbiofilm-forming phenotypes. Differential regulation of genes was observed for polysaccharide biosynthesis, secretion systems, and nonribosomal peptide and polyketide synthase (NRPS/PKS) clusters in response to temperature changes. Deletion mutations of biosynthetic gene clusters (BGCs) 2, 11, 14 (syrbactin), and 15 (malleipeptin) in parental and ΔII2523 backgrounds also reveal the contribution of these BGCs to biofilm formation and colony morphology in addition to inhibition of Bacillus subtilis and Rhizoctonia solani. Our findings suggest that II2523 impacts the regulation of genes that contribute to biofilm formation and competition. Characterization of cryptic BGCs under different environmental conditions will allow for a better understanding of the role of secondary metabolites in the context of biofilm formation and microbe-microbe interactions. IMPORTANCE Burkholderia pseudomallei is a saprophytic bacterium residing in the environment that switches to a pathogenic lifestyle during infection of a wide range of hosts. The environmental cues that serve as the stimulus to trigger this change are largely unknown. However, it is well established that the cellular level of c-di-GMP, a secondary signal messenger, controls the switch from growth as planktonic cells to growth as a biofilm. Disrupting the signaling mediated by c-di-GMP allows for a better understanding of the regulation and the contribution of the surface associated and secreted molecules that contribute to the various lifestyles of this organism. The genome of B. pseudomallei also encodes cryptic biosynthetic gene clusters predicted to encode small molecules that potentially contribute to growth as a biofilm, adaptation, and interactions with other organisms. A better understanding of the regulation of these molecules is crucial to understanding how this versatile pathogen alters its lifestyle.
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Affiliation(s)
- Grace I. Borlee
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, Colorado, USA
| | - Mihnea R. Mangalea
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, Colorado, USA
| | - Kevin H. Martin
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, Colorado, USA
| | - Brooke A. Plumley
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, Colorado, USA
| | - Samuel J. Golon
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, Colorado, USA
| | - Bradley R. Borlee
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, Colorado, USA
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Mangalea MR, Borlee BR. The NarX-NarL two-component system regulates biofilm formation, natural product biosynthesis, and host-associated survival in Burkholderia pseudomallei. Sci Rep 2022; 12:203. [PMID: 34997073 PMCID: PMC8742066 DOI: 10.1038/s41598-021-04053-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Accepted: 12/14/2021] [Indexed: 01/10/2023] Open
Abstract
Burkholderia pseudomallei is a saprophytic bacterium endemic throughout the tropics causing severe disease in humans and animals. Environmental signals such as the accumulation of inorganic ions mediates the biofilm forming capabilities and survival of B. pseudomallei. We have previously shown that B. pseudomallei responds to nitrate and nitrite by inhibiting biofilm formation and altering cyclic di-GMP signaling. To better understand the roles of nitrate-sensing in the biofilm inhibitory phenotype of B. pseudomallei, we created in-frame deletions of narX (Bp1026b_I1014) and narL (Bp1026b_I1013), which are adjacent components of a conserved nitrate-sensing two-component system. We observed transcriptional downregulation in key components of the biofilm matrix in response to nitrate and nitrite. Some of the most differentially expressed genes were nonribosomal peptide synthases (NRPS) and/or polyketide synthases (PKS) encoding the proteins for the biosynthesis of bactobolin, malleilactone, and syrbactin, and an uncharacterized cryptic NRPS biosynthetic cluster. RNA expression patterns were reversed in ∆narX and ∆narL mutants, suggesting that nitrate sensing is an important checkpoint for regulating the diverse metabolic changes occurring in the biofilm inhibitory phenotype. Moreover, in a macrophage model of infection, ∆narX and ∆narL mutants were attenuated in intracellular replication, suggesting that nitrate sensing contributes to survival in the host.
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Affiliation(s)
- Mihnea R Mangalea
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, 80523, USA
| | - Bradley R Borlee
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, 80523, USA.
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McMillan IA, Norris MH, Zarzycki-Siek J, Heacock-Kang Y, Sun Z, Borlee BR, Hoang TT. Identification of a PadR-type regulator essential for intracellular pathogenesis of Burkholderia pseudomallei. Sci Rep 2021; 11:10405. [PMID: 34001967 PMCID: PMC8128862 DOI: 10.1038/s41598-021-89852-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Accepted: 04/28/2021] [Indexed: 11/14/2022] Open
Abstract
Burkholderia pseudomallei (Bp) is the causative agent of melioidosis, a disease endemic to the tropics. Melioidosis manifests in various ways ranging from acute skin lesions to pneumonia and, in rare cases, infection of the central nervous system. Bp is a facultative intracellular pathogen and it can infect various cell types. The Bp intracellular lifecycle has been partially elucidated and is highly complex. Herein, we have identified a transcriptional regulator, BP1026B_II1198, that is differentially expressed as Bp transits through host cells. A deletion mutant of BP1026B_II1198 was attenuated in RAW264.7 cell and BALB/c mouse infection. To further characterize the function of this transcriptional regulator, we endeavored to determine the regulon of BP1026B_II1198. RNA-seq analysis showed the global picture of genes regulated while ChIP-seq analysis identified two specific BP1026B_II1198 binding regions on chromosome II. We investigated the transposon mutants of these genes controlled by BP1026B_II1198 and confirmed that these genes contribute to pathogenesis in RAW264.7 murine macrophage cells. Taken together, the data presented here shed light on the regulon of BP1026B_II1198 and its role during intracellular infection and highlights an integral portion of the highly complex regulation network of Bp during host infection.
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Affiliation(s)
- Ian A McMillan
- School of Life Sciences, University of Hawai'i at Mānoa, Honolulu, Hawai'i, USA
| | - Michael H Norris
- School of Life Sciences, University of Hawai'i at Mānoa, Honolulu, Hawai'i, USA
- Department of Geography and Emerging Pathogens Institute, University of Florida, Gainesville, FL, USA
| | - Jan Zarzycki-Siek
- School of Life Sciences, University of Hawai'i at Mānoa, Honolulu, Hawai'i, USA
| | - Yun Heacock-Kang
- School of Life Sciences, University of Hawai'i at Mānoa, Honolulu, Hawai'i, USA
| | - Zhenxin Sun
- School of Life Sciences, University of Hawai'i at Mānoa, Honolulu, Hawai'i, USA
| | - Bradley R Borlee
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, USA
| | - Tung T Hoang
- School of Life Sciences, University of Hawai'i at Mānoa, Honolulu, Hawai'i, USA.
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Huigens RW, Abouelhassan Y, Yang H. Phenazine Antibiotic-Inspired Discovery of Bacterial Biofilm-Eradicating Agents. Chembiochem 2019; 20:2885-2902. [PMID: 30811834 PMCID: PMC7325843 DOI: 10.1002/cbic.201900116] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Indexed: 12/19/2022]
Abstract
Bacterial biofilms are surface-attached communities of slow-growing and non-replicating persister cells that demonstrate high levels of antibiotic tolerance. Biofilms occur in nearly 80 % of infections and present unique challenges to our current arsenal of antibiotic therapies, all of which were initially discovered for their abilities to target rapidly dividing, free-floating planktonic bacteria. Bacterial biofilms are credited as the underlying cause of chronic and recurring bacterial infections. Innovative approaches are required to identify new small molecules that operate through bacterial growth-independent mechanisms to effectively eradicate biofilms. One source of inspiration comes from within the lungs of young cystic fibrosis (CF) patients, who often endure persistent Staphylococcus aureus infections. As these CF patients age, Pseudomonas aeruginosa co-infects the lungs and utilizes phenazine antibiotics to eradicate the established S. aureus infection. Our group has taken a special interest in this microbial competition strategy and we are investigating the potential of phenazine antibiotic-inspired compounds and synthetic analogues thereof to eradicate persistent bacterial biofilms. To discover new biofilm-eradicating agents, we have established an interdisciplinary research program involving synthetic medicinal chemistry, microbiology and molecular biology. From these efforts, we have identified a series of halogenated phenazines (HPs) that potently eradicate bacterial biofilms, and future work aims to translate these preliminary findings into ground-breaking clinical advances for the treatment of persistent biofilm infections.
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Affiliation(s)
- Robert W. Huigens
- Department of Medicinal Chemistry; Center for Natural Products Drug Discovery and Development (CNPD3); University of Florida, Gainesville, FL, USA
| | - Yasmeen Abouelhassan
- Department of Medicinal Chemistry; Center for Natural Products Drug Discovery and Development (CNPD3); University of Florida, Gainesville, FL, USA
| | - Hongfen Yang
- Department of Medicinal Chemistry; Center for Natural Products Drug Discovery and Development (CNPD3); University of Florida, Gainesville, FL, USA
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Fang X, Wen J, Sun M, Yuan Y, Xu Q. CircRNAs and its relationship with gastric cancer. J Cancer 2019; 10:6105-6113. [PMID: 31762820 PMCID: PMC6856571 DOI: 10.7150/jca.32927] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Accepted: 08/18/2019] [Indexed: 01/17/2023] Open
Abstract
Circular RNAs (circRNAs), as a type of tissue specific RNA with more stable structure than linear RNAs, was poorly understood on its correlation with gastric cancer (GC). In this review, we outline the synthesis and characteristics of circRNAs and generalize their categories and functions. Through comprehensive analysis of the reported results, we find that circRNAs not only participate in the regulation of gastric cancer (GC) cell biological behaviors, such as proliferation, invasion, migration and epithelial mesenchymal transition (EMT), but also are related to the clinicopathological features of GC such as tumor differentiation, TNM stage and metastasis, etc. According to the present screening and verification results, circRNAs are suggested to be used as biomarkers for the early diagnosis and prognosis prediction of GC, and those circRNAs involved in the genesis and development of GC have the potential as novel targets for the individualized treatment of GC.
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Affiliation(s)
- Xinxin Fang
- Tumor Etiology and Screening Department of Cancer Institute and General Surgery, the First Hospital of China Medical University, and Key Laboratory of Cancer Etiology and Prevention (China Medical University), Liaoning Provincial Education Department, Shenyang, China.,Department of Gastroenterology, First Affiliated Hospital, China Medical University, Shenyang City, Liaoning Province, China
| | - Jing Wen
- Tumor Etiology and Screening Department of Cancer Institute and General Surgery, the First Hospital of China Medical University, and Key Laboratory of Cancer Etiology and Prevention (China Medical University), Liaoning Provincial Education Department, Shenyang, China.,Department of Gastroenterology, First Affiliated Hospital, China Medical University, Shenyang City, Liaoning Province, China
| | - Mingjun Sun
- Department of Gastroenterology, First Affiliated Hospital, China Medical University, Shenyang City, Liaoning Province, China.,Key Laboratory of Gastrointestinal Cancer Etiology and Screening, Liaoning Province, Shenyang 110001, China
| | - Yuan Yuan
- Tumor Etiology and Screening Department of Cancer Institute and General Surgery, the First Hospital of China Medical University, and Key Laboratory of Cancer Etiology and Prevention (China Medical University), Liaoning Provincial Education Department, Shenyang, China.,Key Laboratory of Gastrointestinal Cancer Etiology and Screening, Liaoning Province, Shenyang 110001, China
| | - Qian Xu
- Tumor Etiology and Screening Department of Cancer Institute and General Surgery, the First Hospital of China Medical University, and Key Laboratory of Cancer Etiology and Prevention (China Medical University), Liaoning Provincial Education Department, Shenyang, China.,Key Laboratory of Gastrointestinal Cancer Etiology and Screening, Liaoning Province, Shenyang 110001, China
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A Coordinated Response at The Transcriptome and Interactome Level is Required to Ensure Uropathogenic Escherichia coli Survival during Bacteremia. Microorganisms 2019; 7:microorganisms7090292. [PMID: 31450662 PMCID: PMC6780601 DOI: 10.3390/microorganisms7090292] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 08/22/2019] [Accepted: 08/24/2019] [Indexed: 02/03/2023] Open
Abstract
Localized infections or disruption of the skin barrier can enable the entry of bacteria into the bloodstream, possibly leading to acute inflammation and sepsis. There is currently no holistic view on how bacteria can survive and spread in the bloodstream. In this context, we combined transposon mutagenesis, gene-expression profiling and a protein interaction network analysis to examine how uropathogenic Escherichia coli can proliferate in blood. Our results indicate that, upon migration from the urea to serum, E. coli reacts to the osmolarity difference, triggering a transcriptomic response in order to express survival genes. The proteins codified by these genes are precisely organized at the interactome level and specifically target short linear motifs located in disordered regions of host proteins. Such a coordinated response helps to explain how bacteria can adapt to and survive environmental changes within the host. Overall, our results provide a general framework for the study of bacteremia and reveal new targets for potential study as novel antimicrobials.
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Silué N, Marcantonio E, Campbell-Valois FX. RNA-Seq analysis of the T3SA regulon in Shigella flexneri reveals two new chromosomal genes upregulated in the on-state. Methods 2019; 176:71-81. [PMID: 30905752 DOI: 10.1016/j.ymeth.2019.03.017] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Revised: 03/11/2019] [Accepted: 03/20/2019] [Indexed: 02/06/2023] Open
Abstract
Shigella spp. are enterobacteria that invade human colonic mucosal cells using their Type Three Secretion Apparatus (T3SA). Shigella spp. possess a large plasmid that encodes most of its virulence factors and has been the focus of seminal work that defined the T3SA regulon. Thus, a global assessment of the transcriptional response regulated by the T3SA has been lacking. Herein we used RNA-Seq to identify genes that are differentially expressed when the T3SA is active (on-state) versus inactive (off-state). The quality of the RNA-Seq dataset was validated by its correlation with a prior microarray study. Using novel insights about the expression of non-coding regions, bioinformatic tools and experimentations, we demonstrated the existence of six operons and evidence that ipaH2.5 is a pseudogene. In addition, 86 chromosomal genes were downregulated in the on-state including several non-coding transcripts corresponding to short antisense RNA embedded in the 16S and 23S RNA genes, and 40 coding transcripts, whose cognate proteins were highly connected at the genetic and biochemical levels. Finally, we identified two novel chromosomal genes dubbed gem1 and gem3, which were upregulated in the on-state similarly to genes belonging to the T3SA regulon. The latter findings were validated on biological triplicates by droplet digital PCR. To our knowledge gem1 and gem3 are the first chromosomal members of the T3SA regulon that have no homologs on the plasmid. Our approach provides a path to optimizing RNA-Seq studies in case of bacterial models that had previously been the subject of medium to large scale studies.
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Affiliation(s)
- Navoun Silué
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada
| | - Endrei Marcantonio
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada
| | - F-X Campbell-Valois
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada; Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada.
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Abouelhassan Y, Zhang Y, Jin S, Huigens RW. Transcript Profiling of MRSA Biofilms Treated with a Halogenated Phenazine Eradicating Agent: A Platform for Defining Cellular Targets and Pathways Critical to Biofilm Survival. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201809785] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Yasmeen Abouelhassan
- Department of Medicinal ChemistryCenter for Natural Products, Drug Discovery and Development (CNPD3)College of PharmacyUniversity of Florida 1345 Center Drive Gainesville FL USA
| | - Yanping Zhang
- Interdisciplinary Center for Biotechnology Research (ICBR)Gene Expression and GenotypingUniversity of Florida USA
| | - Shouguang Jin
- Department of Molecular Genetics and Microbiology, College of MedicineUniversity of Florida USA
| | - Robert W. Huigens
- Department of Medicinal ChemistryCenter for Natural Products, Drug Discovery and Development (CNPD3)College of PharmacyUniversity of Florida 1345 Center Drive Gainesville FL USA
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Abouelhassan Y, Zhang Y, Jin S, Huigens RW. Transcript Profiling of MRSA Biofilms Treated with a Halogenated Phenazine Eradicating Agent: A Platform for Defining Cellular Targets and Pathways Critical to Biofilm Survival. Angew Chem Int Ed Engl 2018; 57:15523-15528. [PMID: 30230671 DOI: 10.1002/anie.201809785] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2018] [Indexed: 01/09/2023]
Abstract
Bacterial biofilms are surface-attached communities of non-replicating bacteria innately tolerant to antibiotics. Biofilms display differential gene expression profiles and physiologies as compared to their planktonic counterparts; however, their biology remains largely unknown. In this study, we used a halogenated phenazine (HP) biofilm eradicator in transcript profiling experiments (RNA-seq) to define cellular targets and pathways critical to biofilm viability. WoPPER analysis with time-course validation (RT-qPCR) revealed that HP-14 induces rapid iron starvation in MRSA biofilms, as evident by the activation of iron-acquisition gene clusters in 1 hour. Serine proteases and oligopeptide transporters were also found to be up-regulated, whereas glycolysis, arginine deiminase, and urease gene clusters were down-regulated. KEGG analysis revealed that HP-14 impacts metabolic and ABC transporter functional pathways. These findings suggest that MRSA biofilm viability relies on iron homeostasis.
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Affiliation(s)
- Yasmeen Abouelhassan
- Department of Medicinal Chemistry, Center for Natural Products, Drug Discovery and Development (CNPD3), College of Pharmacy, University of Florida, 1345 Center Drive, Gainesville, FL, USA
| | - Yanping Zhang
- Interdisciplinary Center for Biotechnology Research (ICBR), Gene Expression and Genotyping, University of Florida, USA
| | - Shouguang Jin
- Department of Molecular Genetics and Microbiology, College of Medicine, University of Florida, USA
| | - Robert W Huigens
- Department of Medicinal Chemistry, Center for Natural Products, Drug Discovery and Development (CNPD3), College of Pharmacy, University of Florida, 1345 Center Drive, Gainesville, FL, USA
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