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Fan X, Zhao B, Zhang W, Li N, Mi K, Wang B. Coevolution of furA-Regulated Hyper-Inflammation and Mycobacterial Resistance to Oxidative Killing through Adaptation to Hydrogen Peroxide. Microbiol Spectr 2023; 11:e0536722. [PMID: 37358434 PMCID: PMC10433983 DOI: 10.1128/spectrum.05367-22] [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: 12/31/2022] [Accepted: 05/25/2023] [Indexed: 06/27/2023] Open
Abstract
Mycobacterium tuberculosis (Mtb) is highly resistant to host oxidative killing. We hypothesized that the evolutionary adaptation of M. smegmatis to hydrogen peroxide (H2O2) would endow the nonpathogenic Mycobacterium persistent in a host. In the study, we screened a highly H2O2-resistant strain (mc2114) via evolutionary H2O2 adaptation in vitro. The MIC of mc2114 to H2O2 is 320 times that of wild-type mc2155. Mouse infection experiments showed that mc2114, similar to Mtb, was persistent in the lungs and caused high lethality in mice with restricted responses of NOX2, ROS, IFN-γ, decreased macrophage apoptosis, and overexpressed inflammatory cytokines in the lungs. Whole-genome sequencing analysis revealed that mc2114 harbored 29 single nucleotide polymorphisms in multiple genes; one of them was on the furA gene that caused FurA deficiency-mediated overexpression of KatG, a catalase-peroxidase to detoxify ROS. Complementation of mc2114 with a wild-type furA gene reversed lethality and hyper-inflammatory response in mice with rescued overexpression of KatG and inflammatory cytokines, whereas NOX2, ROS, IFN-γ, and macrophage apoptosis remained reduced. The results indicate that although FurA regulates KatG expression, it does not contribute significantly to the restriction of ROS response. Instead, FurA deficiency is responsible for the detrimental pulmonary inflammation that contributes to the severity of the infection, a previously nonrecognized function of FurA in mycobacterial pathogenesis. The study also indicates that mycobacterial resistance to oxidative burst results from complex mechanisms involving adaptive genetic changes in multiple genes. IMPORTANCE Mycobacterium tuberculosis (Mtb) causes human tuberculosis (TB), which has killed more people in human history than any other microorganism. However, the mechanisms underlying Mtb pathogenesis and related genes have not yet been fully elucidated, which impedes the development of effective strategies for containing and eradicating TB. In the study, we generated a mutant of M. smegmatis (mc2114) with multiple mutations by an adaptive evolutionary screen with H2O2. One of the mutations in furA caused a deficiency of FurA, which mediated severe inflammatory lung injury and higher lethality in mice by overexpression of inflammatory cytokines. Our results indicate that FurA-regulated pulmonary inflammation plays a critical role in mycobacterial pathogenesis in addition to the known downregulation of NOX2, ROS, IFN-γ responses, and macrophage apoptosis. Further analysis of the mutations in mc2114 would identify more genes related to the increased pathogenicity and help in devising new strategies for containing and eradicating TB.
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Affiliation(s)
- Xin Fan
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Bei Zhao
- Savaid Medical School, University of Chinese Academy of Sciences, Beijing, China
| | - Weishan Zhang
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
- Savaid Medical School, University of Chinese Academy of Sciences, Beijing, China
| | - Ning Li
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Kaixia Mi
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
- Savaid Medical School, University of Chinese Academy of Sciences, Beijing, China
| | - Beinan Wang
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
- Savaid Medical School, University of Chinese Academy of Sciences, Beijing, China
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Guo L, Mao Q, He J, Liu X, Piao X, Luo L, Hao X, Yu H, Song Q, Xiao B, Fan D, Gao Z, Jia Y. Disruption of ER ion homeostasis maintained by an ER anion channel CLCC1 contributes to ALS-like pathologies. Cell Res 2023; 33:497-515. [PMID: 37142673 PMCID: PMC10313822 DOI: 10.1038/s41422-023-00798-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Accepted: 03/14/2023] [Indexed: 05/06/2023] Open
Abstract
Although anion channel activities have been demonstrated in sarcoplasmic reticulum/endoplasmic reticulum (SR/ER), their molecular identities and functions remain unclear. Here, we link rare variants of Chloride Channel CLIC Like 1 (CLCC1) to amyotrophic lateral sclerosis (ALS)-like pathologies. We demonstrate that CLCC1 is a pore-forming component of an ER anion channel and that ALS-associated mutations impair channel conductance. CLCC1 forms homomultimers and its channel activity is inhibited by luminal Ca2+ but facilitated by phosphatidylinositol 4,5-bisphosphate (PIP2). We identified conserved residues D25 and D181 in CLCC1 N-terminus responsible for Ca2+ binding and luminal Ca2+-mediated inhibition on channel open probability and K298 in CLCC1 intraluminal loop as the critical PIP2-sensing residue. CLCC1 maintains steady-state [Cl-]ER and [K+]ER and ER morphology and regulates ER Ca2+ homeostasis, including internal Ca2+ release and steady-state [Ca2+]ER. ALS-associated mutant forms of CLCC1 increase steady-state [Cl-]ER and impair ER Ca2+ homeostasis, and animals with the ALS-associated mutations are sensitized to stress challenge-induced protein misfolding. Phenotypic comparisons of multiple Clcc1 loss-of-function alleles, including ALS-associated mutations, reveal a CLCC1 dosage dependence in the severity of disease phenotypes in vivo. Similar to CLCC1 rare variations dominant in ALS, 10% of K298A heterozygous mice developed ALS-like symptoms, pointing to a mechanism of channelopathy dominant-negatively induced by a loss-of-function mutation. Conditional knockout of Clcc1 cell-autonomously causes motor neuron loss and ER stress, misfolded protein accumulation, and characteristic ALS pathologies in the spinal cord. Thus, our findings support that disruption of ER ion homeostasis maintained by CLCC1 contributes to ALS-like pathologies.
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Affiliation(s)
- Liang Guo
- Tsinghua-Peking Joint Center for Life Sciences, Tsinghua University, Beijing, China
- School of Life Sciences, Tsinghua University, Beijing, China
- School of Medicine, Tsinghua University, Beijing, China
- IDG/McGovern Institute for Brain Research, Tsinghua University, Beijing, China
| | - Qionglei Mao
- CAS Key Laboratory of Receptor Research, State Key Laboratory of Drug Research, Shanghai Institute of Materia and Medica, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Ji He
- Department of Neurology, Peking University Third Hospital, Beijing, China
| | - Xiaoling Liu
- IDG/McGovern Institute for Brain Research, Tsinghua University, Beijing, China
- School of Pharmaceutical Sciences, Tsinghua University, Beijing, China
| | - Xuejiao Piao
- Tsinghua-Peking Joint Center for Life Sciences, Tsinghua University, Beijing, China
- School of Life Sciences, Tsinghua University, Beijing, China
- School of Medicine, Tsinghua University, Beijing, China
- IDG/McGovern Institute for Brain Research, Tsinghua University, Beijing, China
| | - Li Luo
- School of Medicine, Tsinghua University, Beijing, China
- Tsinghua Laboratory of Brain and Intelligence, Beijing, China
| | - Xiaoxu Hao
- CAS Key Laboratory of Receptor Research, State Key Laboratory of Drug Research, Shanghai Institute of Materia and Medica, Chinese Academy of Sciences, Shanghai, China
- School of Pharmaceutical Sciences, Zhejiang University, Hangzhou, Zhejiang, China
- School of Medicine, Zhejiang University City College, Hangzhou, Zhejiang, China
| | - Hanzhi Yu
- School of Life Sciences, Tsinghua University, Beijing, China
| | - Qiang Song
- School of Medicine, Tsinghua University, Beijing, China
| | - Bailong Xiao
- Tsinghua-Peking Joint Center for Life Sciences, Tsinghua University, Beijing, China
- IDG/McGovern Institute for Brain Research, Tsinghua University, Beijing, China
- School of Pharmaceutical Sciences, Tsinghua University, Beijing, China
| | - Dongsheng Fan
- Department of Neurology, Peking University Third Hospital, Beijing, China.
- Beijing Municipal Key Laboratory of Biomarker and Translational Research in Neurodegenerative Diseases, Beijing, China.
| | - Zhaobing Gao
- CAS Key Laboratory of Receptor Research, State Key Laboratory of Drug Research, Shanghai Institute of Materia and Medica, Chinese Academy of Sciences, Shanghai, China.
- University of Chinese Academy of Sciences, Beijing, China.
| | - Yichang Jia
- Tsinghua-Peking Joint Center for Life Sciences, Tsinghua University, Beijing, China.
- School of Medicine, Tsinghua University, Beijing, China.
- IDG/McGovern Institute for Brain Research, Tsinghua University, Beijing, China.
- Tsinghua Laboratory of Brain and Intelligence, Beijing, China.
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3
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Rowan NJ, Kremer T, McDonnell G. A review of Spaulding's classification system for effective cleaning, disinfection and sterilization of reusable medical devices: Viewed through a modern-day lens that will inform and enable future sustainability. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 878:162976. [PMID: 36963674 DOI: 10.1016/j.scitotenv.2023.162976] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2022] [Revised: 02/23/2023] [Accepted: 03/17/2023] [Indexed: 05/13/2023]
Abstract
Despite advances in medicine and innovations in many underpinning fields including disease prevention and control, the Spaulding classification system, originally proposed in 1957, remains widely used for defining the disinfection and sterilization of contaminated re-usable medical devices and surgical instruments. Screening PubMed and Scopus databases using a PRISMA guiding framework generated 272 relevant publications that were used in this review. Findings revealed that there is a need to evolve how medical devices are designed, and processed by cleaning, disinfection (and/or sterilization) to mitigate patient risks, including acquiring an infection. This Spaulding Classification remains in use as it is logical, easily applied and understood by users (microbiologists, epidemiologists, manufacturers, industry) and by regulators. However, substantial changes have occurred over the past 65 years that challenge interpretation and application of this system that includes inter alia emergence of new pathogens (viruses, mycobacteria, protozoa, fungi), a greater understanding of innate and adaptive microbial tolerance to disinfection, toxicity risks, increased number of vulnerable patients and associated patient procedures, and greater complexity in design and use of medical devices. Common cited examples include endoscopes that enable non- or minimal invasive procedures but are highly sophisticated with various types of materials (polymers, electronic components etc), long narrow channels, right angle and heat-sensitive components and various accessories (e.g., values) that can be contaminated with high levels of microbial bioburden and patient tissues after use. Contaminated flexible duodenoscopes have been a source of several significant infection outbreaks, where at least 9 reported cases were caused by multidrug resistant organisms [MDROs] with no obvious breach in processing detected. Despite this, there is evidence of the lack of attention to cleaning and maintenance of these devices and associated equipment. Over the last few decades there is increasing genomic evidence of innate and adaptive resistance to chemical disinfectant methods along with adaptive tolerance to environmental stresses. To reduce these risks, it has been proposed to elevate classification of higher-risk flexible endoscopes (such as duodenoscopes) from semi-critical [contact with mucous membrane and intact skin] to critical use [contact with sterile tissue and blood] that entails a transition to using low-temperature sterilization modalities instead of routinely using high-level disinfection; thus, increasing the margin of safety for endoscope processing. This timely review addresses important issues surrounding use of the Spaulding classification system to meet modern-day needs. It specifically addresses the need for automated, robust cleaning and drying methods combined with using real-time monitoring of device processing. There is a need to understand entire end-to-end processing of devices instead of adopting silo approaches that in the future will be informed by artificial intelligence and deep-learning/machine learning. For example, combinational solutions that address the formation of complex biofilms that harbour pathogenic and opportunistic microorganisms on the surfaces of processed devices. Emerging trends are addressed including future sustainability for the medical devices sector that can be enabled via a new Quintuple Helix Hub approach that combines academia, industry, healthcare, regulators, and society to unlock real world solutions.
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Affiliation(s)
- N J Rowan
- Centre for Sustainable Disinfection and Sterilization, Bioscience Research Institute, Technological University of the Shannon Midlands Midwest, Athlone Campus, Ireland; Department of Nursing and Healthcare, Technological University of the Shannon Midwest Mideast, Athlone Campus, Ireland; SFI-funded CURAM Centre for Medical Device Research, University of Galway, Ireland.
| | - T Kremer
- Centre for Sustainable Disinfection and Sterilization, Bioscience Research Institute, Technological University of the Shannon Midlands Midwest, Athlone Campus, Ireland; Microbiological Quality & Sterility Assurance, Johnson & Johnson, 1000 Route 202, South Raritan, NJ 08869, USA
| | - G McDonnell
- Microbiological Quality & Sterility Assurance, Johnson & Johnson, 1000 Route 202, South Raritan, NJ 08869, USA
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Wu RA, Feng J, Yue M, Liu D, Ding T. Overuse of food-grade disinfectants threatens a global spread of antimicrobial-resistant bacteria. Crit Rev Food Sci Nutr 2023; 64:6870-6879. [PMID: 36756870 DOI: 10.1080/10408398.2023.2176814] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
Abstract
Food-grade disinfectants are extensively used for microbial decontamination of food processing equipment. In recent years, food-grade disinfectants have been increasingly used. However, the overuse of disinfectants causes another major issue, which is the emergence and spread of antimicrobial-resistant bacteria on a global scale. As the ongoing pandemic takes global attention, bacterial infections with antibiotic resistance are another ongoing pandemic that often goes unnoticed and will be the next real threat to humankind. Here, the effects of food-grade disinfectant overuse on the global emergence and spread of antimicrobial-resistant bacteria were reviewed. It was found that longtime exposure to the most common food-grade disinfectants promoted resistance to clinically important antibiotics in pathogenic bacteria, namely cross-resistance. Currently, the use of disinfectants is largely unregulated. The mechanisms of cross-resistance are regulated by intrinsic molecular mechanisms including efflux pumps, DNA repair system, modification of the molecular target, and metabolic adaptation. Cross-resistance can also be acquired by mobile genetic elements. Long-term exposure to disinfectants has an impact on the dissemination of antimicrobial resistance in soil, plants, animals, water, and human gut environments.
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Affiliation(s)
- Ricardo A Wu
- College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, China
| | - Jinsong Feng
- College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, China
| | - Min Yue
- College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - Donghong Liu
- College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, China
- Ningbo Research Institute, Zhejiang University, Ningbo, China
| | - Tian Ding
- College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, China
- Ningbo Research Institute, Zhejiang University, Ningbo, China
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Lagage V, Chen V, Uphoff S. Adaptation delay causes a burst of mutations in bacteria responding to oxidative stress. EMBO Rep 2022; 24:e55640. [PMID: 36397732 PMCID: PMC9827559 DOI: 10.15252/embr.202255640] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 10/26/2022] [Accepted: 10/28/2022] [Indexed: 11/19/2022] Open
Abstract
Understanding the interplay between phenotypic and genetic adaptation is a focus of evolutionary biology. In bacteria, the oxidative stress response prevents mutagenesis by reactive oxygen species (ROS). We hypothesise that the stress response dynamics can therefore affect the timing of the mutation supply that fuels genetic adaptation to oxidative stress. We uncover that sudden hydrogen peroxide stress causes a burst of mutations. By developing single-molecule and single-cell microscopy methods, we determine how these mutation dynamics arise from phenotypic adaptation mechanisms. H2 O2 signalling by the transcription factor OxyR rapidly induces ROS-scavenging enzymes. However, an adaptation delay leaves cells vulnerable to the mutagenic and toxic effects of hydroxyl radicals generated by the Fenton reaction. Resulting DNA damage is counteracted by a spike in DNA repair activities during the adaptation delay. Absence of a mutation burst in cells with prior stress exposure or constitutive OxyR activation shows that the timing of phenotypic adaptation directly controls stress-induced mutagenesis. Similar observations for alkylation stress show that mutation bursts are a general phenomenon associated with adaptation delays.
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Affiliation(s)
| | - Victor Chen
- Department of BiochemistryUniversity of OxfordOxfordUK
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Jiang Z, Zhuang Z, Mi K. Experimental Evolution Reveals Redox State Modulates Mycobacterial Pathogenicity. Front Genet 2022; 13:758304. [PMID: 35368697 PMCID: PMC8965865 DOI: 10.3389/fgene.2022.758304] [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: 08/13/2021] [Accepted: 02/10/2022] [Indexed: 11/19/2022] Open
Abstract
Understanding how Mycobacterium tuberculosis has evolved into a professional pathogen is helpful in studying its pathogenesis and for designing vaccines. We investigated how the evolutionary adaptation of M. smegmatis mc251 to an important clinical stressor H2O2 allows bacteria to undergo coordinated genetic mutations, resulting in increased pathogenicity. Whole-genome sequencing identified a mutation site in the fur gene, which caused increased expression of katG. Using a Wayne dormancy model, mc251 showed a growth advantage over its parental strain mc2155 in recovering from dormancy under anaerobic conditions. Meanwhile, the high level of KatG in mc251 was accompanied by a low level of ATP, which meant that mc251 is at a low respiratory level. Additionally, the redox-related protein Rv1996 showed different phenotypes in different specific redox states in M. smegmatis mc2155 and mc251, M. bovis BCG, and M. tuberculosis mc27000. In conclusion, our study shows that the same gene presents different phenotypes under different physiological conditions. This may partly explain why M. smegmatis and M. tuberculosis have similar virulence factors and signaling transduction systems such as two-component systems and sigma factors, but due to the different redox states in the corresponding bacteria, M. smegmatis is a nonpathogen, while M. tuberculosis is a pathogen. As mc251 overcomes its shortcomings of rapid removal, it can potentially be developed as a vaccine vector.
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Affiliation(s)
- Zheng Jiang
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
- Savaid Medical School, University of Chinese Academy of Sciences, Beijing, China
| | - Zengfang Zhuang
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
- Savaid Medical School, University of Chinese Academy of Sciences, Beijing, China
| | - Kaixia Mi
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
- Savaid Medical School, University of Chinese Academy of Sciences, Beijing, China
- *Correspondence: Kaixia Mi,
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Hu X, Zhou X, Yin T, Chen K, Hu Y, Zhu B, Mi K. The Mycobacterial DNA Methyltransferase HsdM Decreases Intrinsic Isoniazid Susceptibility. Antibiotics (Basel) 2021; 10:antibiotics10111323. [PMID: 34827261 PMCID: PMC8614780 DOI: 10.3390/antibiotics10111323] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Revised: 10/26/2021] [Accepted: 10/26/2021] [Indexed: 02/02/2023] Open
Abstract
Tuberculosis, caused by the pathogen Mycobacterium tuberculosis, is a serious infectious disease worldwide. Multidrug-resistant TB (MDR-TB) remains a global problem, and the understanding of this resistance is incomplete. Studies suggested that DNA methylation promotes bacterial adaptability to antibiotic treatment, but the role of mycobacterial HsdM in drug susceptibility has not been explored. Here, we constructed an inactivated Mycobacterium bovis (BCG) strain, ΔhsdM. ΔhsdM shows growth advantages over wild-type BCG under isoniazid treatment and hypoxia-induced stress. Using high-precision PacBio single-molecule real-time sequencing to compare the ΔhsdM and BCG methylomes, we identified 219 methylated HsdM substrates. Bioinformatics analysis showed that most HsdM-modified genes were enriched in respiration- and energy-related pathways. qPCR showed that HsdM-modified genes directly affected their own transcription, indicating an altered redox regulation. The use of the latent Wayne model revealed that ΔhsdM had growth advantages over wild-type BCG and that HsdM regulated trcR mRNA levels, which may be crucial in regulating transition from latency to reactivation. We found that HsdM regulated corresponding transcription levels via gene methylation; thus, altering the mycobacterial redox status and decreasing the bacterial susceptibility to isoniazid, which is closely correlated with the redox status. Our results provide valuable insight into DNA methylation on drug susceptibility.
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Affiliation(s)
- Xinling Hu
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; (X.H.); (X.Z.); (T.Y.); (K.C.); (B.Z.)
| | - Xintong Zhou
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; (X.H.); (X.Z.); (T.Y.); (K.C.); (B.Z.)
| | - Tong Yin
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; (X.H.); (X.Z.); (T.Y.); (K.C.); (B.Z.)
| | - Keyu Chen
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; (X.H.); (X.Z.); (T.Y.); (K.C.); (B.Z.)
- Savaid Medical School, University of Chinese Academy of Sciences, Beijing 101408, China
| | - Yongfei Hu
- State Key Laboratory of Animal Nutrition, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China;
| | - Baoli Zhu
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; (X.H.); (X.Z.); (T.Y.); (K.C.); (B.Z.)
- Savaid Medical School, University of Chinese Academy of Sciences, Beijing 101408, China
| | - Kaixia Mi
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; (X.H.); (X.Z.); (T.Y.); (K.C.); (B.Z.)
- Savaid Medical School, University of Chinese Academy of Sciences, Beijing 101408, China
- Correspondence: ; Tel.: +86-01-64806082
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Khan M, Hou S, Azam S, Lei H. Sequence-dependent recruitment of SRSF1 and SRSF7 to intronless lncRNA NKILA promotes nuclear export via the TREX/TAP pathway. Nucleic Acids Res 2021; 49:6420-6436. [PMID: 34096602 PMCID: PMC8216466 DOI: 10.1093/nar/gkab445] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2021] [Revised: 05/03/2021] [Accepted: 05/07/2021] [Indexed: 12/19/2022] Open
Abstract
The TREX-TAP pathway is vital for mRNA export. For spliced mRNA, the TREX complex is recruited during splicing; however, for intronless mRNA, recruitment is sequence dependent. However, the export of cytoplasmic long noncoding RNA (lncRNA) is poorly characterized. We report the identification of a cytoplasmic accumulation region (CAR-N) in the intronless lncRNA, NKILA. CAR-N removal led to strong nuclear retention of NKILA, and CAR-N insertion promoted the export of cDNA transcripts. In vitro RNP purification via CAR-N, mass spectrometry, and siRNA screening revealed that SRSF1 and SRSF7 were vital to NKILA export, and identified a cluster of SRSF1/7 binding sites within a 55 nucleotide sequence in CAR-N. Significant nuclear enrichment of NKILA was observed for NKILA lacking CAR-N or the cluster of binding sites in knock-in models. Depletion of TREX-TAP pathway components resulted in strong nuclear retention of NKILA. RNA and protein immunoprecipitation verified that SRSF1/7 were bound to NKILA and interacted with UAP56 and ALYREF. Moreover, NKILA lacking CAR-N was unable to inhibit breast cancer cell migration. We concluded that the binding of SRSF1/7 to clustered motifs in CAR-N facilitated TREX recruitment, promoting the export of NKILA, and confirmed the importance of NKILA localization to its function.
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Affiliation(s)
- Misbah Khan
- Institute of Cancer Stem Cell, Cancer Center, Dalian Medical University, 9 West Section, Lvshun South Rd, Dalian 116044, P.R. China
| | - Shuai Hou
- Institute of Cancer Stem Cell, Cancer Center, Dalian Medical University, 9 West Section, Lvshun South Rd, Dalian 116044, P.R. China.,School of Food Science and Technology, Dalian Polytechnic University, Dalian 1160343, P.R. China
| | - Sikandar Azam
- Institute of Cancer Stem Cell, Cancer Center, Dalian Medical University, 9 West Section, Lvshun South Rd, Dalian 116044, P.R. China.,Department of Microbial Pathogenesis and Immunology, Texas A&M Health Science Center, Bryan, USA
| | - Haixin Lei
- Institute of Cancer Stem Cell, Cancer Center, Dalian Medical University, 9 West Section, Lvshun South Rd, Dalian 116044, P.R. China
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Pang S, Daley DA, Sahibzada S, Mowlaboccus S, Stegger M, Coombs GW. Genome-wide association studies reveal candidate genes associated to bacteraemia caused by ST93-IV CA-MRSA. BMC Genomics 2021; 22:418. [PMID: 34090342 PMCID: PMC8180019 DOI: 10.1186/s12864-021-07738-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Accepted: 05/25/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The global emergence of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) has seen the dominance of specific clones in different regions around the world with the PVL-positive ST93-IV as the predominant CA-MRSA clone in Australia. In this study we applied a genome-wide association study (GWAS) approach on a collection of Australian ST93-IV MRSA genomes to screen for genetic traits that might have assisted the ongoing transmission of ST93-IV in Australia. We also compared the genomes of ST93-IV bacteraemia and non-bacteraemia isolates to search for potential virulence genes associated with bacteraemia. RESULTS Based on single nucleotide polymorphism phylogenetics we revealed two distinct ST93-IV clades circulating concurrently in Australia. One of the clades contained isolates primarily isolated in the northern regions of Australia whilst isolates in the second clade were distributed across the country. Analyses of the ST93-IV genome plasticity over a 15-year period (2002-2017) revealed an observed gain in accessory genes amongst the clone's population. GWAS analysis on the bacteraemia isolates identified two gene candidates that have previously been associated to this kind of infection. CONCLUSIONS Although this hypothesis was not tested here, it is possible that the emergence of a ST93-IV clade containing additional virulence genes might be related to the high prevalence of ST93-IV infections amongst the indigenous population living in the northern regions of Australia. More importantly, our data also demonstrated that GWAS can reveal candidate genes for further investigations on the pathogenesis and evolution of MRSA strains within a same lineage.
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Affiliation(s)
- Stanley Pang
- Antimicrobial Resistance and Infectious Diseases (AMRID) Research Laboratory, Murdoch University, Murdoch, Western Australia, Australia.
- Department of Microbiology, PathWest Laboratory Medicine-WA, Fiona Stanley Hospital, Murdoch, Western Australia, Australia.
| | - Denise A Daley
- Australian Group on Antimicrobial Resistance (AGAR), Fiona Stanley Hospital, Murdoch, Australia
| | - Shafi Sahibzada
- Antimicrobial Resistance and Infectious Diseases (AMRID) Research Laboratory, Murdoch University, Murdoch, Western Australia, Australia
| | - Shakeel Mowlaboccus
- Antimicrobial Resistance and Infectious Diseases (AMRID) Research Laboratory, Murdoch University, Murdoch, Western Australia, Australia
| | - Marc Stegger
- Antimicrobial Resistance and Infectious Diseases (AMRID) Research Laboratory, Murdoch University, Murdoch, Western Australia, Australia
- Department of Bacteria, Parasites and Fungi, Statens Serum Institut, Copenhagen, Denmark
| | - Geoffrey W Coombs
- Antimicrobial Resistance and Infectious Diseases (AMRID) Research Laboratory, Murdoch University, Murdoch, Western Australia, Australia
- Department of Microbiology, PathWest Laboratory Medicine-WA, Fiona Stanley Hospital, Murdoch, Western Australia, Australia
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10
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Ethanol in Combination with Oxidative Stress Significantly Impacts Mycobacterial Physiology. J Bacteriol 2020; 202:JB.00222-20. [PMID: 32928928 DOI: 10.1128/jb.00222-20] [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: 04/24/2020] [Accepted: 09/02/2020] [Indexed: 11/20/2022] Open
Abstract
Here, we investigate the mycobacterial response to the combined stress of an organic oxidant (cumene hydroperoxide [CHP]) and a solvent (ethanol). To understand the interaction between the two stressors, we treated Mycobacterium smegmatis cells to a range of ethanol concentrations (2.5% to 10% [vol/vol]) in combination with a subinhibitory concentration of 1 mM CHP. It was observed that the presence of CHP increases the efficacy of ethanol in inducing rapid cell death. The data further suggest that ethanol reacts with the alkoxy radicals to produce ethanol-derived peroxides. These radicals induce significant membrane damage and lead to cell lysis. The ethanol-derived radicals were primarily recognized by the cells as organic radicals, as was evident by the differential upregulation of the ohr-ohrR genes that function in cells treated with the combination of ethanol and CHP. The role of organic peroxide reductase, Ohr, was further confirmed by the significantly higher sensitivity of the deletion mutant to CHP and the combined stress treatment of CHP and ethanol. Moreover, we also observed the sigma factor σB to be important for the cells treated with ethanol alone as well as the aforementioned combination. A ΔsigB mutant strain had significantly higher susceptibility to the stress conditions. This finding was correlated with the σB-dependent transcriptional regulation of ohr and ohrR In summary, our data indicate that the combination of low levels of ethanol and organic peroxides induce ethanol-derived organic radicals that lead to significant oxidative stress on the cells in a concentration-dependent manner.IMPORTANCE Bacterial response to a combination of stresses can be unexpected and very different compared with that of an individual stress treatment. This study explores the physiological and transcriptional response of mycobacteria in response to the combinatorial treatment of an oxidant with the commonly used solvent ethanol. The presence of a subinhibitory concentration of organic peroxide increases the effectiveness of ethanol by inducing reactive peroxides that destroy the membrane integrity of cells in a significantly short time span. Our work elucidates a mechanism of targeting the complex mycobacterial membrane, which is its primary source of intrinsic resistance. Furthermore, it also demonstrates the importance of exploring the effect of various stress conditions on inducing bacterial clearance.
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Azam S, Hou S, Zhu B, Wang W, Hao T, Bu X, Khan M, Lei H. Nuclear retention element recruits U1 snRNP components to restrain spliced lncRNAs in the nucleus. RNA Biol 2019; 16:1001-1009. [PMID: 31107149 DOI: 10.1080/15476286.2019.1620061] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
Abstract
In contrast to cytoplasmic localization of spliced mRNAs, many spliced lncRNAs are localized in the nucleus. To investigate the mechanism, we used lncRNA MEG3 as a reporter and mapped a potent nuclear retention element (NRE), deletion of this element led to striking export of MEG3 from the nucleus to the cytoplasm. Insertion of the NRE resulted in nuclear retention of spliced lncRNA as well as spliced mRNA. We further purified RNP assembled on the NRE in vitro and identified the proteins by mass spectrometry. Screen using siRNA revealed depletion of U1 snRNP components SNRPA, SNRNP70 or SNRPD2 caused significant cytoplasmic localization of MEG3 reporter transcripts. Co-knockdown these factors in HFF1 cells resulted in an increased cytoplasmic distribution of endogenous lncRNAs. Together, these data support a model that U1 snRNP components restrain spliced lncRNAs in the nucleus via the interaction with nuclear retention element.
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Affiliation(s)
- Sikandar Azam
- a Institute of Cancer Stem Cell, Cancer Center , Dalian Medical University , Dalian , P.R. China
| | - Shuai Hou
- a Institute of Cancer Stem Cell, Cancer Center , Dalian Medical University , Dalian , P.R. China
| | - Baohui Zhu
- a Institute of Cancer Stem Cell, Cancer Center , Dalian Medical University , Dalian , P.R. China
| | - Weijie Wang
- a Institute of Cancer Stem Cell, Cancer Center , Dalian Medical University , Dalian , P.R. China
| | - Tian Hao
- a Institute of Cancer Stem Cell, Cancer Center , Dalian Medical University , Dalian , P.R. China
| | - Xiangxue Bu
- a Institute of Cancer Stem Cell, Cancer Center , Dalian Medical University , Dalian , P.R. China
| | - Misbah Khan
- a Institute of Cancer Stem Cell, Cancer Center , Dalian Medical University , Dalian , P.R. China
| | - Haixin Lei
- a Institute of Cancer Stem Cell, Cancer Center , Dalian Medical University , Dalian , P.R. China
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Disulfide-mediated conversion of 8-mer bowl-like protein architecture into three different nanocages. Nat Commun 2019; 10:778. [PMID: 30770832 PMCID: PMC6377661 DOI: 10.1038/s41467-019-08788-9] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Accepted: 01/23/2019] [Indexed: 01/16/2023] Open
Abstract
Constructing different protein nanostructures with high-order discrete architectures by using one single building block remains a challenge. Here, we present a simple, effective disulfide-mediated approach to prepare a set of protein nanocages with different geometries from single building block. By genetically deleting an inherent intra-subunit disulfide bond, we can render the conversion of an 8-mer bowl-like protein architecture (NF-8) into a 24-mer ferritin-like nanocage in solution, while selective insertion of an inter-subunit disulfide bond into NF-8 triggers its conversion into a 16-mer lenticular nanocage. Deletion of the same intra-subunit disulfide bond and insertion of the inter-subunit disulfide bond results in the conversion of NF-8 into a 48-mer protein nanocage in solution. Thus, in the laboratory, simple mutation of one protein building block can generate three different protein nanocages in a manner that is highly reminiscent of natural pentamer building block originating from viral capsids that self-assemble into protein assemblies with different symmetries.
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Jia Q, Hu X, Shi D, Zhang Y, Sun M, Wang J, Mi K, Zhu G. Universal stress protein Rv2624c alters abundance of arginine and enhances intracellular survival by ATP binding in mycobacteria. Sci Rep 2016; 6:35462. [PMID: 27762279 PMCID: PMC5071874 DOI: 10.1038/srep35462] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Accepted: 09/30/2016] [Indexed: 01/05/2023] Open
Abstract
The universal stress protein family is a family of stress-induced proteins. Universal stress proteins affect latency and antibiotic resistance in mycobacteria. Here, we showed that Mycobacterium smegmatis overexpressing M. tuberculosis universal stress protein Rv2624c exhibits increased survival in human monocyte THP-1 cells. Transcriptome analysis suggested that Rv2624c affects histidine metabolism, and arginine and proline metabolism. LC-MS/MS analysis showed that Rv2624c affects the abundance of arginine, a modulator of both mycobacteria and infected THP-1 cells. Biochemical analysis showed that Rv2624c is a nucleotide-binding universal stress protein, and an Rv2624c mutant incapable of binding ATP abrogated the growth advantage in THP-1 cells. Rv2624c may therefore modulate metabolic pathways in an ATP-dependent manner, changing the abundance of arginine and thus increasing survival in THP-1 cells.
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Affiliation(s)
- Qiong Jia
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China
| | - Xinling Hu
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, CAS, Beijing 100101, China.,The Research Institute of Forestry, Chinese Academy of Forestry, Beijing 100091, China
| | - Dawei Shi
- Key Laboratory of the Ministry of Health for Research on Quality and Standardization of Biotech Products, National Institutes for Food and Drug Control, Beijing 100050, China
| | - Yan Zhang
- Zhangjiakou Center for Adverse Drug Reaction and Drug Abuse, Hebei 075000, China
| | - Meihao Sun
- College of Chemistry and Life Sciences, Zhejiang Normal University, Zhejiang 321004, China
| | - Jianwei Wang
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China
| | - Kaixia Mi
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, CAS, Beijing 100101, China
| | - Guofeng Zhu
- Shanghai Municipal Center for Disease Control &Prevention, Shanghai 200336, China
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Differential roles of the hemerythrin-like proteins of Mycobacterium smegmatis in hydrogen peroxide and erythromycin susceptibility. Sci Rep 2015; 5:16130. [PMID: 26607739 PMCID: PMC4660385 DOI: 10.1038/srep16130] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Accepted: 10/08/2015] [Indexed: 11/09/2022] Open
Abstract
Hemerythrin-like proteins are oxygen-carrying non-heme di-iron binding proteins and their functions have effect on oxidation-reduction regulation and antibiotic resistance. Recent studies using bioinformatic analyses suggest that multiple hemerythrin-like protein coding sequences might have been acquired by lateral gene transfer and the number of hemerythrin-like proteins varies amongst different species. Mycobacterium smegmatis contains three hemerythrin-like proteins, MSMEG_3312, MSMEG_2415 and MSMEG_6212. In this study, we have systematically analyzed all three hemerythrin-like proteins in M. smegmatis and our results identified and characterized two functional classes: MSMEG_2415 plays an important role in H2O2 susceptibility, and MSMEG_3312 and MSMEG_6212 are associated with erythromycin susceptibility. Phylogenetic analysis indicated that these three proteins have different evolutionary origins, possibly explaining their different physiological functions. Here, combined with biological and phylogenetic analyses, our results provide new insights into the evolutionary divergence of the hemerythrin-like proteins in M. smegmatis.
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Luthuli BB, Purdy GE, Balagaddé FK. Confinement-Induced Drug-Tolerance in Mycobacteria Mediated by an Efflux Mechanism. PLoS One 2015; 10:e0136231. [PMID: 26295942 PMCID: PMC4546595 DOI: 10.1371/journal.pone.0136231] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2015] [Accepted: 07/30/2015] [Indexed: 11/20/2022] Open
Abstract
Tuberculosis (TB) is the world's deadliest curable disease, responsible for an estimated 1.5 million deaths annually. A considerable challenge in controlling this disease is the prolonged multidrug chemotherapy (6 to 9 months) required to overcome drug-tolerant mycobacteria that persist in human tissues, although the same drugs can sterilize genetically identical mycobacteria growing in axenic culture within days. An essential component of TB infection involves intracellular Mycobacterium tuberculosis bacteria that multiply within macrophages and are significantly more tolerant to antibiotics compared to extracellular mycobacteria. To investigate this aspect of human TB, we created a physical cell culture system that mimics confinement of replicating mycobacteria, such as in a macrophage during infection. Using this system, we uncovered an epigenetic drug-tolerance phenotype that appears when mycobacteria are cultured in space-confined bioreactors and disappears in larger volume growth contexts. Efflux mechanisms that are induced in space-confined growth environments contribute to this drug-tolerance phenotype. Therefore, macrophage-induced drug tolerance by mycobacteria may be an effect of confined growth among other macrophage-specific mechanisms.
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Affiliation(s)
- Brilliant B. Luthuli
- KwaZulu-Natal Research Institute for Tuberculosis and HIV, Nelson R. Mandela School of Medicine, University of KwaZulu-Natal, Durban, 4001, South Africa
| | - Georgiana E. Purdy
- Dept. of Molecular Microbiology and Immunology, Oregon Health and Sciences University, 3181 S. W. Sam Jackson Park Rd., Mail Code L220, Portland, OR, 97239, United States of America
| | - Frederick K. Balagaddé
- KwaZulu-Natal Research Institute for Tuberculosis and HIV, Nelson R. Mandela School of Medicine, University of KwaZulu-Natal, Durban, 4001, South Africa
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Li X, Wu J, Han J, Hu Y, Mi K. Distinct Responses of Mycobacterium smegmatis to Exposure to Low and High Levels of Hydrogen Peroxide. PLoS One 2015. [PMID: 26225431 PMCID: PMC4520597 DOI: 10.1371/journal.pone.0134595] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Hydrogen peroxide (H2O2) is a natural oxidant produced by aerobic organisms and gives rise to oxidative damage, including DNA mutations, protein inactivation and lipid damage. The genus Mycobacterium utilizes redox sensors and H2O2 scavenging enzymes for the detoxification of H2O2. To date, the precise response to oxidative stress has not been fully elucidated. Here, we compared the effects of different levels of H2O2 on transcription in M. smegmatis using RNA-sequencing. A 0.2 mM H2O2 treatment had little effect on the growth and viability of M. smegmatis whereas 7 mM H2O2 was lethal. Analysis of global transcription showed that 0.2 mM H2O2 induced relatively few changes in gene expression, whereas a large proportion of the mycobacterial genome was found to be differentially expressed after treatment with 7 mM H2O2. Genes differentially expressed following treatment with 0.2 mM H2O2 included those coding for proteins involved in glycolysis-gluconeogenesis and fatty acid metabolism pathways, and expression of most genes encoding ribosomal proteins was lower following treatment with 7 mM H2O2. Our analysis shows that M. smegmatis utilizes the sigma factor MSMEG_5214 in response to 0.2 mM H2O2, and the RpoE1 sigma factors MSMEG_0573 and MSMEG_0574 in response to 7 mM H2O2. In addition, different transcriptional regulators responded to different levels of H2O2: MSMEG_1919 was induced by 0.2 mM H2O2, while high-level induction of DevR occurred in response to 7 mM H2O2. We detected the induction of different detoxifying enzymes, including genes encoding KatG, AhpD, TrxB and Trx, at different levels of H2O2 and the detoxifying enzymes were expressed at different levels of H2O2. In conclusion, our study reveals the changes in transcription that are induced in response to different levels of H2O2 in M. smegmatis.
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Affiliation(s)
- Xiaojing Li
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, CAS, Beijing, 100101, China
- Beijing Key Laboratory of Microbial Drug Resistance and Resistome, Beijing 100101, Beijing, China
| | - Jun Wu
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, CAS, Beijing, 100101, China
- Beijing Key Laboratory of Microbial Drug Resistance and Resistome, Beijing 100101, Beijing, China
| | - Jiao Han
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, CAS, Beijing, 100101, China
| | - Yongfei Hu
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, CAS, Beijing, 100101, China
- Beijing Key Laboratory of Microbial Drug Resistance and Resistome, Beijing 100101, Beijing, China
| | - Kaixia Mi
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, CAS, Beijing, 100101, China
- Beijing Key Laboratory of Microbial Drug Resistance and Resistome, Beijing 100101, Beijing, China
- * E-mail:
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Miotto P, Cirillo DM, Migliori GB. Drug resistance in Mycobacterium tuberculosis: molecular mechanisms challenging fluoroquinolones and pyrazinamide effectiveness. Chest 2015; 147:1135-1143. [PMID: 25846529 DOI: 10.1378/chest.14-1286] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Physicians are more and more often challenged by difficult-to-treat cases of TB. They include patients infected by strains of Mycobacterium tuberculosis that are resistant to at least isoniazid and rifampicin (multidrug-resistant TB) or to at least one fluoroquinolone (FQ) and one injectable, second-line anti-TB drug in addition to isoniazid and rifampicin (extensively drug-resistant TB). The drug treatment of these cases is very long, toxic, and expensive, and, unfortunately, the proportion of unsatisfactory outcomes is still considerably high. Although FQs and pyrazinamide (PZA) are backbone drugs in the available anti-TB regimens, several uncertainties remain about their mechanisms of action and even more remain about the mechanisms leading to drug resistance. From a clinical point of view, a better understanding of the genetic basis of drug resistance will aid (1) clinicians to provide quality clinical management to both drug-susceptible and drug-resistant TB cases (while preventing emergence of further resistance), and (2) developers of new molecular-based diagnostic assays to better direct their research efforts toward a new generation of sensitive, specific, cheap, and easy-to-use point-of-care diagnostics. In this review we provide an update on the molecular mechanisms leading to FQ- and PZA-resistance in M tuberculosis.
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Affiliation(s)
- Paolo Miotto
- Emerging Bacterial Pathogens Unit, Division of Immunology, Transplantation and Infectious Diseases, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Daniela M Cirillo
- Emerging Bacterial Pathogens Unit, Division of Immunology, Transplantation and Infectious Diseases, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Giovanni Battista Migliori
- WHO Collaborating Centre for TB and Lung Diseases, Fondazione S. Maugeri, Care and Research Institute, Tradate, Italy.
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Hu X, Li X, Huang L, Chan J, Chen Y, Deng H, Mi K. Quantitative proteomics reveals novel insights into isoniazid susceptibility in mycobacteria mediated by a universal stress protein. J Proteome Res 2015; 14:1445-54. [PMID: 25664397 DOI: 10.1021/pr5011058] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Tuberculosis (TB) is caused by the ancient pathogen, Mycobacterium tuberculosis, and is one of the most serious infectious diseases in the world. Isoniazid (INH) is an important first-line drug for the treatment of active and latent TB. INH resistance is an increasing problem in the treatment of TB. Phenotypic resistance to INH, however, is poorly understood. In this study, we constructed a strain of Mycobacterium bovis BCG that overexpresses the latency-related universal stress protein (USP), BCG_2013, and designated this strain BCG-2013. BCG_2013 overexpression increased susceptibility to INH compared with that of the wild-type strain, BCG-pMV261. Quantitative proteomic analysis revealed that BCG_2013 overexpression resulted in the upregulation of 50 proteins and the downregulation of 26 proteins among the 1500 proteins identified. Upregulation of catalase-peroxidase KatG expression in BCG-2013 was observed and confirmed by qPCR, whereas expression of other INH resistance-related proteins did not change. In addition, differential expression of the mycobacterial persistence regulator MprA and its regulatory proteins was observed. BCG_2013 and katG mRNA levels increased in a Wayne dormancy model, whereas MprA mRNA levels decreased. Taken together, our results suggest that the increase in KatG levels induced by increased BCG_2013 levels underlies the phenotypic susceptibility of mycobacteria to INH.
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Affiliation(s)
- Xinling Hu
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, CAS , Beijing 100101, China
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