1
|
Bundhoo E, Ghoorah AW, Jaufeerally-Fakim Y. Large-scale Pan Genomic Analysis of Mycobacterium tuberculosis Reveals Key Insights Into Molecular Evolutionary Rate of Specific Processes and Functions. Evol Bioinform Online 2024; 20:11769343241239463. [PMID: 38532808 PMCID: PMC10964447 DOI: 10.1177/11769343241239463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Accepted: 02/28/2024] [Indexed: 03/28/2024] Open
Abstract
Mycobacterium tuberculosis (Mtb) is the causative agent of tuberculosis (TB), an infectious disease that is a major killer worldwide. Due to selection pressure caused by the use of antibacterial drugs, Mtb is characterised by mutational events that have given rise to multi drug resistant (MDR) and extensively drug resistant (XDR) phenotypes. The rate at which mutations occur is an important factor in the study of molecular evolution, and it helps understand gene evolution. Within the same species, different protein-coding genes evolve at different rates. To estimate the rates of molecular evolution of protein-coding genes, a commonly used parameter is the ratio dN/dS, where dN is the rate of non-synonymous substitutions and dS is the rate of synonymous substitutions. Here, we determined the estimated rates of molecular evolution of select biological processes and molecular functions across 264 strains of Mtb. We also investigated the molecular evolutionary rates of core genes of Mtb by computing the dN/dS values, and estimated the pan genome of the 264 strains of Mtb. Our results show that the cellular amino acid metabolic process and the kinase activity function evolve at a significantly higher rate, while the carbohydrate metabolic process evolves at a significantly lower rate for M. tuberculosis. These high rates of evolution correlate well with Mtb physiology and pathogenicity. We further propose that the core genome of M. tuberculosis likely experiences varying rates of molecular evolution which may drive an interplay between core genome and accessory genome during M. tuberculosis evolution.
Collapse
Affiliation(s)
- Eshan Bundhoo
- Department of Agricultural & Food Science, Faculty of Agriculture, University of Mauritius, Reduit, Mauritius
| | - Anisah W Ghoorah
- Department of Digital Technologies, Faculty of Information, Communication & Digital Technologies, University of Mauritius, Reduit, Mauritius
| | - Yasmina Jaufeerally-Fakim
- Department of Agricultural & Food Science, Faculty of Agriculture, University of Mauritius, Reduit, Mauritius
| |
Collapse
|
2
|
Stanley S, Wang X, Liu Q, Kwon YY, Frey AM, Hicks ND, Vickers AJ, Hui S, Fortune SM. Ongoing evolution of the Mycobacterium tuberculosis lactate dehydrogenase reveals the pleiotropic effects of bacterial adaption to host pressure. PLoS Pathog 2024; 20:e1012050. [PMID: 38422159 DOI: 10.1371/journal.ppat.1012050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Revised: 03/12/2024] [Accepted: 02/13/2024] [Indexed: 03/02/2024] Open
Abstract
The bacterial determinants that facilitate Mycobacterium tuberculosis (Mtb) adaptation to the human host environment are poorly characterized. We have sought to decipher the pressures facing the bacterium in vivo by assessing Mtb genes that are under positive selection in clinical isolates. One of the strongest targets of selection in the Mtb genome is lldD2, which encodes a quinone-dependent L-lactate dehydrogenase (LldD2) that catalyzes the oxidation of lactate to pyruvate. Lactate accumulation is a salient feature of the intracellular environment during infection and lldD2 is essential for Mtb growth in macrophages. We determined the extent of lldD2 variation across a set of global clinical isolates and defined how prevalent mutations modulate Mtb fitness. We show the stepwise nature of lldD2 evolution that occurs as a result of ongoing lldD2 selection in the background of ancestral lineage-defining mutations and demonstrate that the genetic evolution of lldD2 additively augments Mtb growth in lactate. Using quinone-dependent antibiotic susceptibility as a functional reporter, we also find that the evolved lldD2 mutations functionally increase the quinone-dependent activity of LldD2. Using 13C-lactate metabolic flux tracing, we find that lldD2 is necessary for robust incorporation of lactate into central carbon metabolism. In the absence of lldD2, label preferentially accumulates in dihydroxyacetone phosphate (DHAP) and glyceraldehyde-3-phosphate (G3P) and is associated with a discernible growth defect, providing experimental evidence for accrued lactate toxicity via the deleterious buildup of sugar phosphates. The evolved lldD2 variants increase lactate incorporation to pyruvate while altering triose phosphate flux, suggesting both an anaplerotic and detoxification benefit to lldD2 evolution. We further show that the mycobacterial cell is transcriptionally sensitive to the changes associated with altered lldD2 activity which affect the expression of genes involved in cell wall lipid metabolism and the ESX- 1 virulence system. Together, these data illustrate a multifunctional role of LldD2 that provides context for the selective advantage of lldD2 mutations in adapting to host stress.
Collapse
Affiliation(s)
- Sydney Stanley
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, United States of America
| | - Xin Wang
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, United States of America
| | - Qingyun Liu
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, United States of America
| | - Young Yon Kwon
- Department of Molecular Metabolism, Harvard T. H. Chan School of Public Health, Boston, Massachusetts, United States of America
| | - Abigail M Frey
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, United States of America
| | - Nathan D Hicks
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, United States of America
| | - Andrew J Vickers
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, United States of America
| | - Sheng Hui
- Department of Molecular Metabolism, Harvard T. H. Chan School of Public Health, Boston, Massachusetts, United States of America
| | - Sarah M Fortune
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, United States of America
- Ragon Institute of MGH, MIT, and Harvard, Cambridge, Massachusetts, United States of America
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| |
Collapse
|
3
|
Rubinstein M, Makhon A, Losev Y, Valenci GZ, Gatt YE, Margalit H, Fass E, Kutikov I, Murik O, Zeevi DA, Savyon M, Tau L, Kaidar Shwartz H, Dveyrin Z, Rorman E, Nissan I. Prolonged survival of a patient with active MDR-TB HIV co-morbidity: insights from a Mycobacterium tuberculosis strain with a unique genomic deletion. Front Med (Lausanne) 2023; 10:1292665. [PMID: 38020140 PMCID: PMC10657812 DOI: 10.3389/fmed.2023.1292665] [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: 09/11/2023] [Accepted: 10/16/2023] [Indexed: 12/01/2023] Open
Abstract
Coinfection of HIV and multidrug-resistant tuberculosis (MDR-TB) presents significant challenges in terms of the treatment and prognosis of tuberculosis, leading to complexities in managing the disease and impacting the overall outcome for TB patients. This study presents a remarkable case of a patient with MDR-TB and HIV coinfection who survived for over 8 years, despite poor treatment adherence and comorbidities. Whole genome sequencing (WGS) of the infecting Mycobacterium tuberculosis (Mtb) strain revealed a unique genomic deletion, spanning 18 genes, including key genes involved in hypoxia response, intracellular survival, immunodominant antigens, and dormancy. This deletion, that we have called "Del-X," potentially exerts a profound influence on the bacterial physiology and its virulence. Only few similar deletions were detected in other non-related Mtb genomes worldwide. In vivo evolution analysis identified drug resistance and metabolic adaptation mutations and their temporal dynamics during the patient's treatment course.
Collapse
Affiliation(s)
- Mor Rubinstein
- National Public Health Laboratory, Public Health Directorate, Ministry of Health, Tel Aviv, Israel
| | - Andrei Makhon
- National Public Health Laboratory, Public Health Directorate, Ministry of Health, Tel Aviv, Israel
| | - Yelena Losev
- National Public Health Laboratory, Public Health Directorate, Ministry of Health, Tel Aviv, Israel
| | - Gal Zizelski Valenci
- National Public Health Laboratory, Public Health Directorate, Ministry of Health, Tel Aviv, Israel
| | - Yair E. Gatt
- Department of Microbiology and Molecular Genetics, Institute for Medical Research Israel-Canada, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Hanah Margalit
- Department of Microbiology and Molecular Genetics, Institute for Medical Research Israel-Canada, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Ephraim Fass
- National Public Health Laboratory, Public Health Directorate, Ministry of Health, Tel Aviv, Israel
| | - Ina Kutikov
- National Public Health Laboratory, Public Health Directorate, Ministry of Health, Tel Aviv, Israel
| | - Omer Murik
- Translational Genomics Laboratory, Medical Genetics Institute, Shaare Zedek Medical Center, Jerusalem, Israel
| | - David A. Zeevi
- Translational Genomics Laboratory, Medical Genetics Institute, Shaare Zedek Medical Center, Jerusalem, Israel
| | - Michal Savyon
- Tel Aviv District Health Office, Ministry of Health, Tel Aviv, Israel
| | - Luba Tau
- Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
- Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Hasia Kaidar Shwartz
- National Public Health Laboratory, Public Health Directorate, Ministry of Health, Tel Aviv, Israel
| | - Zeev Dveyrin
- National Public Health Laboratory, Public Health Directorate, Ministry of Health, Tel Aviv, Israel
| | - Efrat Rorman
- National Public Health Laboratory, Public Health Directorate, Ministry of Health, Tel Aviv, Israel
| | - Israel Nissan
- National Public Health Laboratory, Public Health Directorate, Ministry of Health, Tel Aviv, Israel
| |
Collapse
|
4
|
Wasai-Hara S, Itakura M, Fernandes Siqueira A, Takemoto D, Sugawara M, Mitsui H, Sato S, Inagaki N, Yamazaki T, Imaizumi-Anraku H, Shimoda Y, Minamisawa K. Bradyrhizobium ottawaense efficiently reduces nitrous oxide through high nosZ gene expression. Sci Rep 2023; 13:18862. [PMID: 37914789 PMCID: PMC10620151 DOI: 10.1038/s41598-023-46019-w] [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: 08/23/2023] [Accepted: 10/26/2023] [Indexed: 11/03/2023] Open
Abstract
N2O is an important greenhouse gas influencing global warming, and agricultural land is the predominant (anthropogenic) source of N2O emissions. Here, we report the high N2O-reducing activity of Bradyrhizobium ottawaense, suggesting the potential for efficiently mitigating N2O emission from agricultural lands. Among the 15 B. ottawaense isolates examined, the N2O-reducing activities of most (13) strains were approximately five-fold higher than that of Bradyrhizobium diazoefficiens USDA110T under anaerobic conditions. This robust N2O-reducing activity of B. ottawaense was confirmed by N2O reductase (NosZ) protein levels and by mitigation of N2O emitted by nodule decomposition in laboratory system. While the NosZ of B. ottawaense and B. diazoefficiens showed high homology, nosZ gene expression in B. ottawaense was over 150-fold higher than that in B. diazoefficiens USDA110T, suggesting the high N2O-reducing activity of B. ottawaense is achieved by high nos expression. Furthermore, we examined the nos operon transcription start sites and found that, unlike B. diazoefficiens, B. ottawaense has two transcription start sites under N2O-respiring conditions, which may contribute to the high nosZ expression. Our study indicates the potential of B. ottawaense for effective N2O reduction and unique regulation of nos gene expression towards the high performance of N2O mitigation in the soil.
Collapse
Affiliation(s)
- Sawa Wasai-Hara
- Institute of Agrobiological Sciences, National Agriculture and Food Research Organization (NARO), Tsukuba, Ibaraki, Japan
- Graduate School of Life Sciences, Tohoku University, Sendai, Miyagi, Japan
| | - Manabu Itakura
- Graduate School of Life Sciences, Tohoku University, Sendai, Miyagi, Japan
| | | | - Daisaku Takemoto
- Research Center for Advanced Analysis, National Agriculture and Food Research Organization (NARO), Tsukuba, Ibaraki, Japan
| | - Masayuki Sugawara
- Graduate School of Life Sciences, Tohoku University, Sendai, Miyagi, Japan
| | - Hisayuki Mitsui
- Graduate School of Life Sciences, Tohoku University, Sendai, Miyagi, Japan
| | - Shusei Sato
- Graduate School of Life Sciences, Tohoku University, Sendai, Miyagi, Japan
| | - Noritoshi Inagaki
- Research Center for Advanced Analysis, National Agriculture and Food Research Organization (NARO), Tsukuba, Ibaraki, Japan
| | - Toshimasa Yamazaki
- Research Center for Advanced Analysis, National Agriculture and Food Research Organization (NARO), Tsukuba, Ibaraki, Japan
| | - Haruko Imaizumi-Anraku
- Institute of Agrobiological Sciences, National Agriculture and Food Research Organization (NARO), Tsukuba, Ibaraki, Japan
| | - Yoshikazu Shimoda
- Institute of Agrobiological Sciences, National Agriculture and Food Research Organization (NARO), Tsukuba, Ibaraki, Japan.
| | - Kiwamu Minamisawa
- Graduate School of Life Sciences, Tohoku University, Sendai, Miyagi, Japan.
| |
Collapse
|
5
|
Stanley S, Wang X, Liu Q, Kwon YY, Frey AM, Hicks ND, Vickers AJ, Hui S, Fortune SM. Ongoing evolution of the Mycobacterium tuberculosis lactate dehydrogenase reveals the pleiotropic effects of bacterial adaption to host pressure. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.09.561592. [PMID: 37873410 PMCID: PMC10592758 DOI: 10.1101/2023.10.09.561592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2023]
Abstract
The bacterial determinants that facilitate Mycobacterium tuberculosis (Mtb) adaptation to the human host environment are poorly characterized. We have sought to decipher the pressures facing the bacterium in vivo by assessing Mtb genes that are under positive selection in clinical isolates. One of the strongest targets of selection in the Mtb genome is lldD2 , which encodes a quinone-dependent L-lactate dehydrogenase (LldD2) that catalyzes the oxidation of lactate to pyruvate. Lactate accumulation is a salient feature of the intracellular environment during infection and lldD2 is essential for Mtb growth in macrophages. We determined the extent of lldD2 variation across a set of global clinical isolates and defined how prevalent mutations modulates Mtb fitness. We show the stepwise nature of lldD2 evolution that occurs as a result of ongoing lldD2 selection in the background of ancestral lineage defining mutations and demonstrate that the genetic evolution of lldD2 additively augments Mtb growth in lactate. Using quinone-dependent antibiotic susceptibility as a functional reporter, we also find that the evolved lldD2 mutations functionally increase the quinone-dependent activity of LldD2. Using 13 C-lactate metabolic flux tracing, we find that lldD2 is necessary for robust incorporation of lactate into central carbon metabolism. In the absence of lldD2 , label preferentially accumulates in methylglyoxal precursors dihydroxyacetone phosphate (DHAP) and glyceraldehyde-3-phosphate (G3P) and is associated with a discernible growth defect, providing experimental evidence for accumulated lactate toxicity via a methylglyoxal pathway that has been proposed previously. The evolved lldD2 variants increase lactate incorporation to pyruvate but also alter flux in the methylglyoxal pathway, suggesting both an anaplerotic and detoxification benefit to lldD2 evolution. We further show that the mycobacterial cell is transcriptionally sensitive to the changes associated with altered lldD2 activity which affect the expression of genes involved in cell wall lipid metabolism and the ESX-1 virulence system. Together, these data illustrate a multifunctional role of LldD2 that provide context for the selective advantage of lldD2 mutations in adapting to host stress.
Collapse
|
6
|
Song Z, Liu C, He W, Pei S, Liu D, Cao X, Wang Y, He P, Zhao B, Ou X, Xia H, Wang S, Zhao Y. Insight into the drug-resistant characteristics and genetic diversity of multidrug-resistant Mycobacterium tuberculosis in China. Microbiol Spectr 2023; 11:e0132423. [PMID: 37732780 PMCID: PMC10581218 DOI: 10.1128/spectrum.01324-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Accepted: 07/16/2023] [Indexed: 09/22/2023] Open
Abstract
Multidrug-resistant tuberculosis (MDR-TB) has a severe impact on public health. To investigate the drug-resistant profile, compensatory mutations and genetic variations among MDR-TB isolates, a total of 546 MDR-TB isolates from China underwent drug-susceptibility testing and whole genome sequencing for further analysis. The results showed that our isolates have a high rate of fluoroquinolone resistance (45.60%, 249/546) and a low proportion of conferring resistance to bedaquiline, clofazimine, linezolid, and delamanid. The majority of MDR-TB isolates (77.66%, 424/546) belong to Lineage 2.2.1, followed by Lineage 4.5 (6.41%, 35/546), and the Lineage 2 isolates have a strong association with pre-XDR/XDR-TB (P < 0.05) in our study. Epidemic success analysis using time-scaled haplotypic density (THD) showed that clustered isolates outperformed non-clustered isolates. Compensatory mutations happened in rpoA, rpoC, and non-RRDR of rpoB genes, which were found more frequently in clusters and were associated with the increase of THD index, suggesting that increased bacterial fitness was associated with MDR-TB transmission. In addition, the variants in resistance associated genes in MDR isolates are mainly focused on single nucleotide polymorphism mutations, and only a few genes have indel variants, such as katG, ethA. We also found some genes underwent indel variation correlated with the lineage and sub-lineage of isolates, suggesting the selective evolution of different lineage isolates. Thus, this analysis of the characterization and genetic diversity of MDR isolates would be helpful in developing effective strategies for treatment regimens and tailoring public interventions. IMPORTANCE Multidrug-resistant tuberculosis (MDR-TB) is a serious obstacle to tuberculosis prevention and control in China. This study provides insight into the drug-resistant characteristics of MDR combined with phenotypic drug-susceptibility testing and whole genome sequencing. The compensatory mutations and epidemic success analysis were analyzed by time-scaled haplotypic density (THD) method, suggesting clustered isolates and compensatory mutations are associated with MDR-TB transmission. In addition, the insertion and deletion variants happened in some genes, which are associated with the lineage and sub-lineage of isolates, such as the mpt64 gene. This study offered a valuable reference and increased understanding of MDR-TB in China, which could be crucial for achieving the objective of precision medicine in the prevention and treatment of MDR-TB.
Collapse
Affiliation(s)
- Zexuan Song
- National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China
- National Tuberculosis Reference Laboratory, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Chunfa Liu
- National Tuberculosis Reference Laboratory, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Wencong He
- National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China
- National Tuberculosis Reference Laboratory, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Shaojun Pei
- School of Public Health, Peking University, Beijing, China
| | - Dongxin Liu
- National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Xiaolong Cao
- National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China
- National Tuberculosis Reference Laboratory, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Yiting Wang
- National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China
- National Tuberculosis Reference Laboratory, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Ping He
- National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China
- National Tuberculosis Reference Laboratory, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Bing Zhao
- National Tuberculosis Reference Laboratory, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Xichao Ou
- National Tuberculosis Reference Laboratory, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Hui Xia
- National Tuberculosis Reference Laboratory, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Shengfen Wang
- National Tuberculosis Reference Laboratory, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Yanlin Zhao
- National Tuberculosis Reference Laboratory, Chinese Center for Disease Control and Prevention, Beijing, China
| |
Collapse
|
7
|
Seah YM, Stewart MK, Hoogestraat D, Ryder M, Cookson BT, Salipante SJ, Hoffman NG. In Silico Evaluation of Variant Calling Methods for Bacterial Whole-Genome Sequencing Assays. J Clin Microbiol 2023; 61:e0184222. [PMID: 37428072 PMCID: PMC10446864 DOI: 10.1128/jcm.01842-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Accepted: 06/18/2023] [Indexed: 07/11/2023] Open
Abstract
Identification and analysis of clinically relevant strains of bacteria increasingly relies on whole-genome sequencing. The downstream bioinformatics steps necessary for calling variants from short-read sequences are well-established but seldom validated against haploid genomes. We devised an in silico workflow to introduce single nucleotide polymorphisms (SNP) and indels into bacterial reference genomes, and computationally generate sequencing reads based on the mutated genomes. We then applied the method to Mycobacterium tuberculosis H37Rv, Staphylococcus aureus NCTC 8325, and Klebsiella pneumoniae HS11286, and used the synthetic reads as truth sets for evaluating several popular variant callers. Insertions proved especially challenging for most variant callers to correctly identify, relative to deletions and single nucleotide polymorphisms. With adequate read depth, however, variant callers that use high quality soft-clipped reads and base mismatches to perform local realignment consistently had the highest precision and recall in identifying insertions and deletions ranging from1 to 50 bp. The remaining variant callers had lower recall values associated with identification of insertions greater than 20 bp.
Collapse
Affiliation(s)
- Yee Mey Seah
- Department of Laboratory Medicine and Pathology, University of Washington Medical Center, Seattle, Washington, USA
| | - Mary K. Stewart
- Department of Laboratory Medicine and Pathology, University of Washington Medical Center, Seattle, Washington, USA
| | - Daniel Hoogestraat
- Department of Laboratory Medicine and Pathology, University of Washington Medical Center, Seattle, Washington, USA
| | - Molly Ryder
- Department of Laboratory Medicine and Pathology, University of Washington Medical Center, Seattle, Washington, USA
| | - Brad T. Cookson
- Department of Laboratory Medicine and Pathology, University of Washington Medical Center, Seattle, Washington, USA
- Department of Microbiology, University of Washington, Seattle, Washington, USA
| | - Stephen J. Salipante
- Department of Laboratory Medicine and Pathology, University of Washington Medical Center, Seattle, Washington, USA
| | - Noah G. Hoffman
- Department of Laboratory Medicine and Pathology, University of Washington Medical Center, Seattle, Washington, USA
| |
Collapse
|
8
|
Dupuy P, Ghosh S, Adefisayo O, Buglino J, Shuman S, Glickman MS. Distinctive roles of translesion polymerases DinB1 and DnaE2 in diversification of the mycobacterial genome through substitution and frameshift mutagenesis. Nat Commun 2022; 13:4493. [PMID: 35918328 PMCID: PMC9346131 DOI: 10.1038/s41467-022-32022-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Accepted: 07/12/2022] [Indexed: 12/15/2022] Open
Abstract
Antibiotic resistance of Mycobacterium tuberculosis is exclusively a consequence of chromosomal mutations. Translesion synthesis (TLS) is a widely conserved mechanism of DNA damage tolerance and mutagenesis, executed by translesion polymerases such as DinBs. In mycobacteria, DnaE2 is the only known agent of TLS and the role of DinB polymerases is unknown. Here we demonstrate that, when overexpressed, DinB1 promotes missense mutations conferring resistance to rifampicin, with a mutational signature distinct from that of DnaE2, and abets insertion and deletion frameshift mutagenesis in homo-oligonucleotide runs. DinB1 is the primary mediator of spontaneous −1 frameshift mutations in homo-oligonucleotide runs whereas DnaE2 and DinBs are redundant in DNA damage-induced −1 frameshift mutagenesis. These results highlight DinB1 and DnaE2 as drivers of mycobacterial genome diversification with relevance to antimicrobial resistance and host adaptation. This manuscript elucidates new mechanisms of mutagenesis in mycobacteria by implicating two translesion DNA polymerases in genome diversification, including creating the mutations that underlie all antibiotic resistance in these global pathogens.
Collapse
Affiliation(s)
- Pierre Dupuy
- Immunology Program, Sloan Kettering Institute, New York, NY, 10065, USA
| | - Shreya Ghosh
- Molecular Biology Program, Sloan-Kettering Institute, New York, NY, 10065, USA
| | - Oyindamola Adefisayo
- Immunology Program, Sloan Kettering Institute, New York, NY, 10065, USA.,Immunology and Microbial Pathogenesis Graduate Program, Weill Cornell Graduate School, 1300 York Avenue, New York, NY, 10065, USA
| | - John Buglino
- Immunology Program, Sloan Kettering Institute, New York, NY, 10065, USA
| | - Stewart Shuman
- Molecular Biology Program, Sloan-Kettering Institute, New York, NY, 10065, USA
| | - Michael S Glickman
- Immunology Program, Sloan Kettering Institute, New York, NY, 10065, USA. .,Immunology and Microbial Pathogenesis Graduate Program, Weill Cornell Graduate School, 1300 York Avenue, New York, NY, 10065, USA.
| |
Collapse
|
9
|
Savino S, Desmet T, Franceus J. Insertions and deletions in protein evolution and engineering. Biotechnol Adv 2022; 60:108010. [PMID: 35738511 DOI: 10.1016/j.biotechadv.2022.108010] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Revised: 06/15/2022] [Accepted: 06/16/2022] [Indexed: 11/17/2022]
Abstract
Protein evolution or engineering studies are traditionally focused on amino acid substitutions and the way these contribute to fitness. Meanwhile, the insertion and deletion of amino acids is often overlooked, despite being one of the most common sources of genetic variation. Recent methodological advances and successful engineering stories have demonstrated that the time is ripe for greater emphasis on these mutations and their understudied effects. This review highlights the evolutionary importance and biotechnological relevance of insertions and deletions (indels). We provide a comprehensive overview of approaches that can be employed to include indels in random, (semi)-rational or computational protein engineering pipelines. Furthermore, we discuss the tolerance to indels at the structural level, address how domain indels can link the function of unrelated proteins, and feature studies that illustrate the surprising and intriguing potential of frameshift mutations.
Collapse
Affiliation(s)
- Simone Savino
- Centre for Synthetic Biology (CSB), Department of Biotechnology, Ghent University, Coupure Links 653, 9000 Ghent, Belgium
| | - Tom Desmet
- Centre for Synthetic Biology (CSB), Department of Biotechnology, Ghent University, Coupure Links 653, 9000 Ghent, Belgium
| | - Jorick Franceus
- Centre for Synthetic Biology (CSB), Department of Biotechnology, Ghent University, Coupure Links 653, 9000 Ghent, Belgium..
| |
Collapse
|
10
|
Ceres KM, Stanhope MJ, Gröhn YT. A critical evaluation of Mycobacterium bovis pangenomics, with reference to its utility in outbreak investigation. Microb Genom 2022; 8. [PMID: 35763423 PMCID: PMC9455707 DOI: 10.1099/mgen.0.000839] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The increased accessibility of next generation sequencing has allowed enough genomes from a given bacterial species to be sequenced to describe the distribution of genes in the pangenome, without limiting analyses to genes present in reference strains. Although some taxa have thousands of whole genome sequences available on public databases, most genomes were sequenced with short read technology, resulting in incomplete assemblies. Studying pangenomes could lead to important insights into adaptation, pathogenicity, or molecular epidemiology, however given the known information loss inherent in analyzing contig-level assemblies, these inferences may be biased or inaccurate. In this study we describe the pangenome of a clonally evolving pathogen,
Mycobacterium bovis
, and examine the utility of gene content variation in
M. bovis
outbreak investigation. We constructed the
M. bovis
pangenome using 1463 de novo assembled genomes. We tested the assumption of strict clonal evolution by studying evidence of recombination in core genes and analyzing the distribution of accessory genes among core monophyletic groups. To determine if gene content variation could be utilized in outbreak investigation, we carefully examined accessory genes detected in a well described
M. bovis
outbreak in Minnesota. We found significant errors in accessory gene classification. After accounting for these errors, we show that
M. bovis
has a much smaller accessory genome than previously described and provide evidence supporting ongoing clonal evolution and a closed pangenome, with little gene content variation generated over outbreaks. We also identified frameshift mutations in multiple genes, including a mutation in glpK, which has recently been associated with antibiotic tolerance in
Mycobacterium tuberculosis
. A pangenomic approach enables a more comprehensive analysis of genome dynamics than is possible with reference-based approaches; however, without critical evaluation of accessory gene content, inferences of transmission patterns employing these loci could be misguided.
Collapse
Affiliation(s)
- Kristina M Ceres
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York, USA.,Population and Ecosystem Health, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
| | - Michael J Stanhope
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York, USA.,Population and Ecosystem Health, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
| | - Yrjö T Gröhn
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York, USA.,Population and Ecosystem Health, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
| |
Collapse
|
11
|
Volk D, Yang-Turner F, Didelot X, Crook DW, Wyllie D. Catwalk: identifying closely related sequences in large microbial sequence databases. Microb Genom 2022; 8. [PMID: 35771206 PMCID: PMC9455716 DOI: 10.1099/mgen.0.000850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
There is a need to identify microbial sequences that may form part of transmission chains, or that may represent importations across national boundaries, amidst large numbers of SARS-CoV-2 and other bacterial or viral sequences. Reference-based compression is a sequence analysis technique that allows both a compact storage of sequence data and comparisons between sequences. Published implementations of the approach are being challenged by the large sample collections now being generated. Our aim was to develop a fast software detecting highly similar sequences in large collections of microbial genomes, including millions of SARS-CoV-2 genomes. To do so, we developed Catwalk, a tool that bypasses bottlenecks in the generation, comparison and in-memory storage of microbial genomes generated by reference mapping. It is a compiled solution, coded in Nim to increase performance. It can be accessed via command line, rest api or web server interfaces. We tested Catwalk using both SARS-CoV-2 and Mycobacterium tuberculosis genomes generated by prospective public-health sequencing programmes. Pairwise sequence comparisons, using clinically relevant similarity cut-offs, took about 0.39 and 0.66 μs, respectively; in 1 s, between 1 and 2 million sequences can be searched. Catwalk operates about 1700 times faster than, and uses about 8 % of the RAM of, a Python reference-based compression and comparison tool in current use for outbreak detection. Catwalk can rapidly identify close relatives of a SARS-CoV-2 or M. tuberculosis genome amidst millions of samples.
Collapse
Affiliation(s)
- Denis Volk
- Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Fan Yang-Turner
- Nuffield Department of Medicine, University of Oxford, Oxford, UK.,Present address: UKRI Science and Technologies Facilities Council, Harwell, UK
| | - Xavier Didelot
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK.,Department of Statistics, University of Warwick, Coventry CV4 7AL, UK
| | - Derrick W Crook
- Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - David Wyllie
- UK Health Security Agency, Forvie Site, Addenbrookes' Campus, Robinson Way, Cambridge CB2 0SR, UK
| |
Collapse
|
12
|
Express Yourself: Quantitative Real-Time PCR Assays for Rapid Chromosomal Antimicrobial Resistance Detection in Pseudomonas aeruginosa. Antimicrob Agents Chemother 2022; 66:e0020422. [PMID: 35467369 DOI: 10.1128/aac.00204-22] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
The rise of antimicrobial-resistant (AMR) bacteria is a global health emergency. One critical facet of tackling this epidemic is more rapid AMR diagnosis in serious multidrug-resistant pathogens like Pseudomonas aeruginosa. Here, we designed and then validated two multiplex quantitative real-time PCR (qPCR) assays to simultaneously detect differential expression of the resistance-nodulation-division efflux pumps MexAB-OprM, MexCD-OprJ, MexEF-OprN, and MexXY-OprM, the AmpC β-lactamase, and the porin OprD, which are commonly associated with chromosomally encoded AMR. Next, qPCRs were tested on 15 sputa from 11 participants with P. aeruginosa respiratory infections to determine AMR profiles in vivo. We confirmed multiplex qPCR testing feasibility directly on sputa, representing a key advancement in in vivo AMR diagnosis. Notably, comparison of sputa with their derived isolates grown in Luria-Bertani broth (±2.5% NaCl) or a 5-antibiotic cocktail showed marked expression differences, illustrating the difficulty in replicating in vivo expression profiles in vitro. Cystic fibrosis sputa showed significantly reduced mexE and mexY expression compared with chronic obstructive pulmonary disease sputa, despite harboring fluoroquinolone- and aminoglycoside-resistant strains, indicating that these loci do not contribute to AMR in vivo. oprD was also significantly downregulated in cystic fibrosis sputa, even in the absence of contemporaneous carbapenem use, suggesting a common adaptive trait in chronic infections that may affect carbapenem efficacy. Sputum ampC expression was highest in participants receiving carbapenems (6.7 to 15×), some of whom were simultaneously receiving cephalosporins, the latter of which would be rendered ineffective by the upregulated ampC. Our qPCR assays provide valuable insights into the P. aeruginosa resistome, and their use on clinical specimens will permit timely treatment alterations that will improve patient outcomes and antimicrobial stewardship measures.
Collapse
|
13
|
Guo S, Lei S, Palittapongarnpim P, McNeil E, Chaiprasert A, Li J, Chen H, Ou W, Surachat K, Qin W, Zhang S, Luo R, Chongsuvivatwong V. Association between Mycobacterium tuberculosis genotype and diabetes mellitus/hypertension: a molecular study. BMC Infect Dis 2022; 22:401. [PMID: 35462543 PMCID: PMC9035274 DOI: 10.1186/s12879-022-07344-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Accepted: 04/05/2022] [Indexed: 11/10/2022] Open
Abstract
Background A paucity of studies focused on the genetic association that tuberculosis (TB) patients with non-communicable diseases (NCDs) are more likely to be infected with Mycobacterium tuberculosis (MTB) with more potent virulence on anti-TB drug resistance than those without NCDs. The study aimed to document the predominant genotype, determine the association between MTB genotypes and NCD status and drug resistance. Methods We conducted a molecular study in 105 TB patients based on a cross-sectional study focused on the comorbid relationship between chronic conditions and TB among 1773 subjects from September 1, 2019 to August 30, 2020 in Guizhou, China. The participants were investigated through face-to-face interviews, followed by NCDs screening. The DNA of MTB isolates was extracted prior to genotyping using 24 loci MIRU-VNTR. The subsequent evaluations were performed by phylogenetic trees, combined with tests of statistical power, Chi-square or Fisher and multivariate logistic regression analysis. Results The Beijing family of Lineage 2 (East Asia) was the predominant genotype accounting for 43.8% (46/105), followed by Lineage 4 (Euro-America) strains, including Uganda I (34.3%, 36/105), and the NEW-1 (9.5%, 10/105). The proportion of Beijing strain in patients with and without NCDS was 28.6% (8/28) and 49.4% (38/77), respectively, with a statistical power test value of 24.3%. No significant association was detected between MTB genotype and NCD status. A low clustering rate (2.9%) was identified, consisting of two clusters. The rates of global, mono-, poly- and multi-drug resistance were 16.2% (17/105), 14.3% (15/105), 1.0% (1/105) and 4.8% (5/105), respectively. The drug-resistant rates of rifampicin, isoniazid, and streptomycin, were 6.7% (7/105), 11.4% (12/105) and 5.7% (6/105), respectively. Isoniazid resistance was significantly associated with the Beijing genotype of Lineage 2 (19.6% versus 5.1%). Conclusions The Lineage 2 East Asia/Beijing genotype is the dominant genotype of the local MTB with endogenous infection preponderating. Not enough evidence is detected to support the association between the MTB genotype and diabetes/hypertension. Isoniazid resistance is associated with the Lineage 2 East Asia/Beijing strain. Supplementary information The online version contains supplementary material available at 10.1186/s12879-022-07344-z.
Collapse
|
14
|
Small Insertions and Deletions Drive Genomic Plasticity during Adaptive Evolution of Yersinia pestis. Microbiol Spectr 2022; 10:e0224221. [PMID: 35438532 PMCID: PMC9248902 DOI: 10.1128/spectrum.02242-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The life cycle of Yersinia pestis has changed a lot to adapt to flea-borne transmission since it evolved from an enteric pathogen, Yersinia pseudotuberculosis. Small insertions and deletions (indels), especially frameshift mutations, can have major effects on phenotypes and contribute to virulence and host adaptation through gene disruption and inactivation. Here, we analyzed 365 Y. pestis genomes and identified 2,092 genome-wide indels on the core genome. As recently reported in Mycobacterium tuberculosis, we also detected "indel pockets" in Y. pestis, with average complexity scores declining around indel positions, which we speculate might also exist in other prokaryotes. Phylogenic analysis showed that indel-based phylogenic tree could basically reflect the phylogenetic relationships of major phylogroups in Y. pestis, except some inconsistency around the Big Bang polytomy. We observed 83 indels arising in the trunk of the phylogeny, which played a role in accumulation of pseudogenes related to key metabolism and putatively pathogenicity. We also discovered 32 homoplasies at the level of phylogroups and 7 frameshift scars (i.e., disrupted reading frame being rescued by a second frameshift). Additionally, our analysis showed evidence of parallel evolution at the level of genes, with sspA, rpoS, rnd, and YPO0624, having enriched mutations in Brazilian isolates, which might be advantageous for Y. pestis to cope with fluctuating environments. The diversified selection signals observed here demonstrates that indels are important contributors to the adaptive evolution of Y. pestis. Meanwhile, we provide potential targets for further exploration, as some genes/pseudogenes with indels we focus on remain uncharacterized. IMPORTANCE Yersinia pestis, the causative agent of plague, is a highly pathogenic clone of Yersinia pseudotuberculosis. Previous genome-wide SNP analysis provided few adaptive signatures during its evolution. Here by investigating 365 public genomes of Y. pestis, we give a comprehensive overview of general features of genome-wide indels on the core genome and their roles in Y. pestis evolution. Detection of "indel pockets," with average complexity scores declining around indel positions, in both Mycobacterium tuberculosis and Y. pestis, gives us a clue that this phenomenon might appear in other bacterial genomes. Importantly, the identification of four different forms of selection signals in indels would improve our understanding on adaptive evolution of Y. pestis, and provide targets for further physiological mechanism researches of this pathogen. As evolutionary research based on genome-wide indels is still rare in bacteria, our study would be a helpful reference in deciphering the role of indels in other species.
Collapse
|
15
|
Pérez-Martínez DE, Bermúdez-Hernández GA, Madrazo-Moya CF, Cancino-Muñoz I, Montero H, Licona-Cassani C, Muñiz-Salazar R, Comas I, Zenteno-Cuevas R. SNPs in Genes Related to DNA Damage Repair in Mycobacterium Tuberculosis: Their Association with Type 2 Diabetes Mellitus and Drug Resistance. Genes (Basel) 2022; 13:genes13040609. [PMID: 35456415 PMCID: PMC9029044 DOI: 10.3390/genes13040609] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 03/19/2022] [Accepted: 03/24/2022] [Indexed: 12/04/2022] Open
Abstract
Genes related to DNA damage repair in Mycobacterium tuberculosis are critical for survival and genomic diversification. The aim of this study is to compare the presence of SNPs in genes related to DNA damage repair in sensitive and drug-resistant M. tuberculosis genomes isolated from patients with and without type 2 diabetes mellitus (T2DM). We collected 399 M. tuberculosis L4 genomes from several public repositories; 224 genomes belonging to hosts without T2DM, of which 123 (54.9%) had drug sensitive tuberculosis (TB) and 101 (45.1%) had drug resistance (DR)-TB; and 175 genomes from individuals with T2DM, of which 100 (57.1%) had drug sensitive TB and 75 (42.9%) had DR-TB. The presence of SNPs in the coding regions of 65 genes related to DNA damage repair was analyzed and compared with the resistance profile and the presence/absence of T2DM in the host. The results show the phylogenetic relationships of some SNPS and L4 sub-lineages, as well as differences in the distribution of SNPs present in DNA damage repair-related genes related to the resistance profile of the infecting strain and the presence of T2DM in the host. Given these differences, it was possible to generate two discriminant functions to distinguish between drug sensitive and drug resistant genomes, as well as patients with or without T2DM.
Collapse
Affiliation(s)
- Damián E. Pérez-Martínez
- Programa de Doctorado en Ciencias de la Salud, Instituto de Ciencias de la Salud, Universidad Veracruzana, Av. Luis, Dr. Castelazo Ayala s/n, Col. Industrial Animas, Xalapa 91190, Mexico; (D.E.P.-M.); (G.A.B.-H.)
| | - Gustavo A. Bermúdez-Hernández
- Programa de Doctorado en Ciencias de la Salud, Instituto de Ciencias de la Salud, Universidad Veracruzana, Av. Luis, Dr. Castelazo Ayala s/n, Col. Industrial Animas, Xalapa 91190, Mexico; (D.E.P.-M.); (G.A.B.-H.)
| | - Carlos F. Madrazo-Moya
- Biomedical Institute of Valencia IBV-CSIC, C. de Jaume Roig, 11, 46010 Valencia, Spain; (C.F.M.-M.); (I.C.-M.); (I.C.)
| | - Irving Cancino-Muñoz
- Biomedical Institute of Valencia IBV-CSIC, C. de Jaume Roig, 11, 46010 Valencia, Spain; (C.F.M.-M.); (I.C.-M.); (I.C.)
- CIBER of Epidemiology and Public Health, 08908 Madrid, Spain
| | - Hilda Montero
- Instituto de Salud Pública, Universidad Veracruzana, Av. Luis Castelazo Ayala s/n, A.P. 57, Col. Industrial Animas, Xalapa 91190, Mexico;
| | - Cuauhtemoc Licona-Cassani
- Escuela de Ingeniería y Ciencias, Tecnológico de Monterrey, Ave. Eugenio Garza Sada 2501 Sur, Monterrey 64849, Mexico;
- Red Multidisciplinaria de Investigación en Tuberculosis, Mexico City 14080, Mexico;
- Division of Integrative Biology, The Institute for Obesity Research, Tecnológico de Monterrey, Monterrey 64849, Mexico
| | - Raquel Muñiz-Salazar
- Red Multidisciplinaria de Investigación en Tuberculosis, Mexico City 14080, Mexico;
- Laboratorio de Epidemiología y Ecología Molecular, Escuela de Ciencias de la Salud, Universidad Autónoma de Baja California, Ensenada 22890, Mexico
| | - Iñaki Comas
- Biomedical Institute of Valencia IBV-CSIC, C. de Jaume Roig, 11, 46010 Valencia, Spain; (C.F.M.-M.); (I.C.-M.); (I.C.)
- CIBER of Epidemiology and Public Health, 08908 Madrid, Spain
| | - Roberto Zenteno-Cuevas
- Instituto de Salud Pública, Universidad Veracruzana, Av. Luis Castelazo Ayala s/n, A.P. 57, Col. Industrial Animas, Xalapa 91190, Mexico;
- Red Multidisciplinaria de Investigación en Tuberculosis, Mexico City 14080, Mexico;
- Correspondence:
| |
Collapse
|
16
|
Swain SS, Pati S, Hussain T. Quinoline heterocyclic containing plant and marine candidates against drug-resistant Mycobacterium tuberculosis: A systematic drug-ability investigation. Eur J Med Chem 2022; 232:114173. [DOI: 10.1016/j.ejmech.2022.114173] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 01/30/2022] [Accepted: 02/02/2022] [Indexed: 12/22/2022]
|
17
|
Goossens SN, Heupink TH, De Vos E, Dippenaar A, De Vos M, Warren R, Van Rie A. Detection of minor variants in Mycobacterium tuberculosis whole genome sequencing data. Brief Bioinform 2021; 23:6484510. [PMID: 34962257 PMCID: PMC8769888 DOI: 10.1093/bib/bbab541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 11/05/2021] [Accepted: 11/24/2021] [Indexed: 11/25/2022] Open
Abstract
The study of genetic minority variants is fundamental to the understanding of complex processes such as evolution, fitness, transmission, virulence, heteroresistance and drug tolerance in Mycobacterium tuberculosis (Mtb). We evaluated the performance of the variant calling tool LoFreq to detect de novo as well as drug resistance conferring minor variants in both in silico and clinical Mtb next generation sequencing (NGS) data. The in silico simulations demonstrated that LoFreq is a conservative variant caller with very high precision (≥96.7%) over the entire range of depth of coverage tested (30x to1000x), independent of the type and frequency of the minor variant. Sensitivity increased with increasing depth of coverage and increasing frequency of the variant, and was higher for calling insertion and deletion (indel) variants than for single nucleotide polymorphisms (SNP). The variant frequency limit of detection was 0.5% and 3% for indel and SNP minor variants, respectively. For serial isolates from a patient with DR-TB; LoFreq successfully identified all minor Mtb variants in the Rv0678 gene (allele frequency as low as 3.22% according to targeted deep sequencing) in whole genome sequencing data (median coverage of 62X). In conclusion, LoFreq can successfully detect minor variant populations in Mtb NGS data, thus limiting the need for filtering of possible false positive variants due to sequencing error. The observed performance statistics can be used to determine the limit of detection in existing whole genome sequencing Mtb data and guide the required depth of future studies that aim to investigate the presence of minor variants.
Collapse
Affiliation(s)
- Sander N Goossens
- Family Medicine and Population Health (FAMPOP), Faculty of Medicine and Health Sciences, University of Antwerp, Wilrijk, Belgium
| | - Tim H Heupink
- Family Medicine and Population Health (FAMPOP), Faculty of Medicine and Health Sciences, University of Antwerp, Wilrijk, Belgium
| | - Elise De Vos
- Family Medicine and Population Health (FAMPOP), Faculty of Medicine and Health Sciences, University of Antwerp, Wilrijk, Belgium
| | - Anzaan Dippenaar
- Family Medicine and Population Health (FAMPOP), Faculty of Medicine and Health Sciences, University of Antwerp, Wilrijk, Belgium
| | | | - Rob Warren
- Department of Science and Innovation-National Research Foundation Centre for Excellence for Biomedical Tuberculosis Research, South African Medical Research Council Centre for Tuberculosis Research, Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, Tygerberg, South Africa
| | - Annelies Van Rie
- Family Medicine and Population Health (FAMPOP), Faculty of Medicine and Health Sciences, University of Antwerp, Wilrijk, Belgium
| |
Collapse
|
18
|
Ciprofloxacin induced antibiotic resistance in Salmonella Typhimurium mutants and genome analysis. Arch Microbiol 2021; 203:6131-6142. [PMID: 34585273 DOI: 10.1007/s00203-021-02577-z] [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: 06/24/2021] [Revised: 09/07/2021] [Accepted: 09/12/2021] [Indexed: 10/20/2022]
Abstract
Antibiotic resistance of Salmonella species is well reported. Ciprofloxacin is the frontline antibiotic for salmonellosis. The repeated exposure to ciprofloxacin leads to resistant strains. After 20 cycles of antibiotic exposure, resistant bacterial clones were evaluated. The colony size of the mutants was small and had an extended lag phase compared to parent strain. The whole genome sequencing showed 40,513 mutations across the genome. Small percentage (5.2%) of mutations was non-synonymous. Four-fold more transitions were observed than transversions. Ratio of < 1 transition vs transversion showed a positive selection for antibiotic resistant trait. Mutation distribution across the genome was uniform. The native plasmid was an exception and 2 mutations were observed on 90 kb plasmid. The important genes like dnaE, gyrA, iroC, metH and rpoB involved in antibiotic resistance had point mutations. The genome analysis revealed most of the metabolic pathways were affected.
Collapse
|