1
|
Rupasinghe P, Ashraf A, Barreda N, Parveen S, Zubair M, Calderon R, Asif S, Hirani N, Chingisova L, Bulane A, Hang PT, Ha DT, Ardizzoni E, Kursheed N, De Rijk WB, Rigouts L, Guglielmetti L, Mitnick C, de Jong BC. Reduced critical concentration might not have improved MGIT-based DST's sensitivity to rifampicin. Antimicrob Agents Chemother 2024; 68:e0170123. [PMID: 38534101 PMCID: PMC11064607 DOI: 10.1128/aac.01701-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/28/2024] Open
Affiliation(s)
- Praharshinie Rupasinghe
- Unit of Mycobacteriology, Institute of Tropical Medicine, Antwerp, Belgium
- Department of Biomedical Sciences, University of Antwerp, Wilrijk, Antwerp, Belgium
| | - Azka Ashraf
- The Indus Hospital laboratory, Karachi, Pakistan
| | | | | | | | | | - Sunil Asif
- The Indus Hospital laboratory, Karachi, Pakistan
| | - Nilma Hirani
- Department of Microbiology, Sir JJ Hospital, Mumbai, India
| | | | - Atang Bulane
- Center for Tuberculosis, National Institute of Communicable Diseases, Mohakhali, South Africa
| | - Pham Thu Hang
- Regional Tuberculosis Reference Lab, Ho Chi Minh, Vietnam
| | - Doan Thu Ha
- National Tuberculosis Reference Lab, Hanoi, Vietnam
| | - Elisa Ardizzoni
- Unit of Mycobacteriology, Institute of Tropical Medicine, Antwerp, Belgium
| | | | | | - Leen Rigouts
- Unit of Mycobacteriology, Institute of Tropical Medicine, Antwerp, Belgium
- Department of Biomedical Sciences, University of Antwerp, Wilrijk, Antwerp, Belgium
| | - Lorenzo Guglielmetti
- Medical Department, MSF, Paris, France
- Sorbonne University, Centre d’Immunologie et des Maladies Infectieuses (Cimi-Paris), Paris, France
- AP-HP, Bactériologie-Hygiène, Hôpital Pitié-Salpêtrière, Centre National de Référence des Mycobactéries, Paris, France
| | - Carol Mitnick
- Brigham and Women's Hospital, Boston, Massachusetts, USA
- Partners In Health, Boston, Massachusetts, USA
- Department of Global Health and Social Medicine, Harvard Medical School, Boston, Massachusetts, USA
| | - Bouke C. de Jong
- Unit of Mycobacteriology, Institute of Tropical Medicine, Antwerp, Belgium
| |
Collapse
|
2
|
Van Nguyen H, Binh Nguyen H, Thu Ha D, Thi Huong D, Ngoc Trung V, Thi Thuy Ngoc K, Huyen Trang T, Vu Thi Ngoc H, Trinh Thi Bich T, Le Pham Tien T, Nguyen Hong H, Phan Trieu P, Kim Lan L, Lan K, Ngoc Hue N, Thi Le Huong N, Le Thi Ngoc Thao T, Le Quang N, Do Dang Anh T, Hữu Lân N, Van Vinh T, Thi Minh Ha D, Thuong Dat P, Phuc Hai N, Crook DW, Thuy Thuong Thuong N, Viet Nguyen N, Thwaites GE, Walker TM. Rifampicin resistant Mycobacterium tuberculosis in Vietnam, 2020-2022. J Clin Tuberc Other Mycobact Dis 2024; 35:100431. [PMID: 38523706 PMCID: PMC10958107 DOI: 10.1016/j.jctube.2024.100431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/26/2024] Open
Abstract
Objective We conducted a descriptive analysis of multi-drug resistant tuberculosis (MDR-TB) in Vietnam's two largest cities, Hanoi and Ho Chi Minh city. Methods All patients with rifampicin resistant tuberculosis were recruited from Hanoi and surrounding provinces between 2020 and 2022. Additional patients were recruited from Ho Chi Minh city over the same time period. Demographic data were recorded from all patients, and samples collected, cultured, whole genome sequenced and analysed for drug resistance mutations. Genomic susceptibility predictions were made on the basis of the World Health Organization's catalogue of mutations in Mycobacterium tuberculosis associated with drug resistance, version 2. Comparisons were made against phenotypic drug susceptibility test results where these were available. Multivariable logistic regression was used to assess risk factors for previous episodes of tuberculosis. Results 233/265 sequenced isolates were of sufficient quality for analysis, 146 (63 %) from Ho Chi Minh City and 87 (37 %) from Hanoi. 198 (85 %) were lineage 2, 20 (9 %) were lineage 4, and 15 (6 %) were lineage 1. 17/211 (8 %) for whom HIV status was known were infected, and 109/214 (51 %) patients had had a previous episode of tuberculosis. The main risk factor for a previous episode was HIV infection (odds ratio 5.1 (95 % confidence interval 1.3-20.0); p = 0.021). Sensitivity for predicting first-line drug resistance from whole genome sequencing data was over 90 %, with the exception of pyrazinamide (85 %). For moxifloxacin and amikacin it was 50 % or less. Among rifampicin-resistant isolates, prevalence of resistance to each non-first-line drug was < 20 %. Conclusions Drug resistance among most MDR-TB strains in Vietnam's two largest cities is confined largely to first-line drugs. Living with HIV is the main risk factor among patients with MDR-TB for having had a previous episode of tuberculosis.
Collapse
Affiliation(s)
- Hung Van Nguyen
- National Lung Hospital, Hanoi, Viet Nam
- Vietnam National University, University of Medicine and Pharmacy, Viet Nam
| | | | | | | | | | | | | | - Ha Vu Thi Ngoc
- Oxford University Clinical Research Unit, Ho Chi Minh City, Viet Nam
| | | | | | - Hanh Nguyen Hong
- Oxford University Clinical Research Unit, Ho Chi Minh City, Viet Nam
| | - Phu Phan Trieu
- Oxford University Clinical Research Unit, Ho Chi Minh City, Viet Nam
| | - Luong Kim Lan
- Oxford University Clinical Research Unit, Ho Chi Minh City, Viet Nam
| | - Kim Lan
- Oxford University Clinical Research Unit, Ho Chi Minh City, Viet Nam
| | - Ngo Ngoc Hue
- Oxford University Clinical Research Unit, Ho Chi Minh City, Viet Nam
| | | | | | - Nguyen Le Quang
- Oxford University Clinical Research Unit, Ho Chi Minh City, Viet Nam
| | - Thu Do Dang Anh
- Oxford University Clinical Research Unit, Ho Chi Minh City, Viet Nam
| | | | | | | | | | | | - Derrick W. Crook
- Nuffield Department of Medicine, University of Oxford, Oxford, UK
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Nguyen Thuy Thuong Thuong
- Oxford University Clinical Research Unit, Ho Chi Minh City, Viet Nam
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Nhung Viet Nguyen
- Vietnam National University, University of Medicine and Pharmacy, Viet Nam
| | - Guy E. Thwaites
- Oxford University Clinical Research Unit, Ho Chi Minh City, Viet Nam
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Timothy M. Walker
- Oxford University Clinical Research Unit, Ho Chi Minh City, Viet Nam
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| |
Collapse
|
3
|
Cuong NK, Thanh DV, Luong DV, Manh The N, Duc Thai T, Tran Thi Tuan A, Thu Ha D, Dat VQ. Histopathological features in the clinical specimens with tuberculosis diagnosis by BACTEC MGIT 960 culture. J Clin Tuberc Other Mycobact Dis 2023; 33:100401. [PMID: 37927571 PMCID: PMC10622830 DOI: 10.1016/j.jctube.2023.100401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2023] Open
Abstract
Diagnosis of extrapulmonary tuberculosis remains challenging in lower-middle income countries with high burden of tuberculosis (TB). This study aims to describe the histological characteristics in biopsy samples from patients with confirmed TB. This is a retrospective study of clinical biopsy specimens with positive liquid medium culture for Mycobacterium tuberculosis and histopathological examination in the National Lung Hospital in Vietnam. Among 1045 biopsy specimens with mycobacteria culture, the overall rate of growth of Mycobacteria tuberculosis in culture was 20.7% (216/1045). The positivity rates of MIGT culture among surgical biopsy specimens were 75% in bone specimen, followed by vertebral specimens (51.3%), and joint specimens (26.4%). For specimens obtained by the fine needle aspiration, the positivity rates of MIGT culture were 26.3% in lymph node and 25.3% in pleural specimen. Among specimens with culture confirmation of TB, the most common histopathoglogical suggestive finding of TB was the presence of epithelioid cell (83.3%), Langhans giant cells (75.9%), and caseous necrosis (75.5%). The high proportion of histological features suggestive of TB among the TB culture confirmed biopsy samples support for further evaluation of histological examination and its combination with other recommended rapid molecular assays in specimens with suspicion of TB.
Collapse
Affiliation(s)
- Nguyen Kim Cuong
- Department of Respiratory Tuberculosis, National Lung Hospital, Hanoi, Vietnam
- Department of Tuberculosis and Lung Diseases, Hanoi Medical University, Hanoi, Vietnam
| | - Dang Van Thanh
- Department of Infectious Diseases, Hanoi Medical University, Hanoi, Vietnam
| | - Dinh Van Luong
- Centre of Lung Transplantation, National Lung Hospital, Hanoi, Vietnam
| | - Nguyen Manh The
- Department of Respiratory Tuberculosis, National Lung Hospital, Hanoi, Vietnam
| | - Truong Duc Thai
- Department of Respiratory Tuberculosis, National Lung Hospital, Hanoi, Vietnam
| | | | - Doan Thu Ha
- Department of Microbiology and National Tuberculosis Reference Laboratory, National Lung Hospital, Hanoi, Vietnam
| | - Vu Quoc Dat
- Department of Infectious Diseases, Hanoi Medical University, Hanoi, Vietnam
- Hanoi Medical University Hospital, Hanoi Medical University, Hanoi, Vietnam
| |
Collapse
|
4
|
Buelo CD, Pace ML, Carpenter SR, Stanley EH, Ortiz DA, Ha DT. Evaluating the performance of temporal and spatial early warning statistics of algal blooms. Ecol Appl 2022; 32:e2616. [PMID: 35368134 DOI: 10.1002/eap.2616] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Accepted: 01/14/2022] [Indexed: 06/14/2023]
Abstract
Regime shifts have large consequences for ecosystems and the services they provide. However, understanding the potential for, causes of, proximity to, and thresholds for regime shifts in nearly all settings is difficult. Generic statistical indicators of resilience have been proposed and studied in a wide range of ecosystems as a method to detect when regime shifts are becoming more likely without direct knowledge of underlying system dynamics or thresholds. These early warning statistics (EWS) have been studied separately but there have been few examples that directly compare temporal and spatial EWS in ecosystem-scale empirical data. To test these methods, we collected high-frequency time series and high-resolution spatial data during a whole-lake fertilization experiment while also monitoring an adjacent reference lake. We calculated two common EWS, standard deviation and autocorrelation, in both time series and spatial data to evaluate their performance prior to the resulting algal bloom. We also applied the quickest detection method to generate binary alarms of resilience change from temporal EWS. One temporal EWS, rolling window standard deviation, provided advanced warning in most variables prior to the bloom, showing trends and between-lake patterns consistent with theory. In contrast, temporal autocorrelation and both measures of spatial EWS (spatial SD, Moran's I) provided little or no warning. By compiling time series data from this and past experiments with and without nutrient additions, we were able to evaluate temporal EWS performance for both constant and changing resilience conditions. True positive alarm rates were 2.5-8.3 times higher for rolling window standard deviation when a lake was being pushed towards a bloom than the rate of false positives when it was not. For rolling window autocorrelation, alarm rates were much lower and no variable had a higher true positive than false positive alarm rate. Our findings suggest temporal EWS provide advanced warning of algal blooms and that this approach could help managers prepare for and/or minimize negative bloom impacts.
Collapse
Affiliation(s)
- C D Buelo
- Department of Environmental Sciences, University of Virginia, Charlottesville, Virginia, USA
- Center for Limnology, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - M L Pace
- Department of Environmental Sciences, University of Virginia, Charlottesville, Virginia, USA
| | - S R Carpenter
- Center for Limnology, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - E H Stanley
- Center for Limnology, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - D A Ortiz
- Center for Limnology, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - D T Ha
- Department of Environmental Sciences, University of Virginia, Charlottesville, Virginia, USA
| |
Collapse
|
5
|
Laksman J, Kooser K, Levola H, Itälä E, Ha DT, Rachlew E, Kukk E. Dissociation pathways in the cysteine dication after site-selective core ionization. J Phys Chem B 2014; 118:11688-95. [PMID: 25233490 DOI: 10.1021/jp508161s] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
A photoelectron-ion-ion coincidence experiment has been carried out on the amino acid molecule cysteine after core-ionization of the O 1s, N 1s, C 1s, and S 2p orbitals. A number of different dissociation channels have been identified. Some of them show strong site-selective dependence that can be attributed to a combination of nuclear motion in the core-ionized state and Auger processes that populate different final electronic states in the dication.
Collapse
Affiliation(s)
- J Laksman
- Department of Physics, University of Oulu , P.O. Box 3000, FIN-90014 Oulu, Finland
| | | | | | | | | | | | | |
Collapse
|
6
|
Murphy BF, Osipov T, Jurek Z, Fang L, Son SK, Mucke M, Eland JHD, Zhaunerchyk V, Feifel R, Avaldi L, Bolognesi P, Bostedt C, Bozek JD, Grilj J, Guehr M, Frasinski LJ, Glownia J, Ha DT, Hoffmann K, Kukk E, McFarland BK, Miron C, Sistrunk E, Squibb RJ, Ueda K, Santra R, Berrah N. Femtosecond X-ray-induced explosion of C60 at extreme intensity. Nat Commun 2014; 5:4281. [PMID: 24969734 DOI: 10.1038/ncomms5281] [Citation(s) in RCA: 108] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2014] [Accepted: 06/02/2014] [Indexed: 11/09/2022] Open
Abstract
Understanding molecular femtosecond dynamics under intense X-ray exposure is critical to progress in biomolecular imaging and matter under extreme conditions. Imaging viruses and proteins at an atomic spatial scale and on the time scale of atomic motion requires rigorous, quantitative understanding of dynamical effects of intense X-ray exposure. Here we present an experimental and theoretical study of C60 molecules interacting with intense X-ray pulses from a free-electron laser, revealing the influence of processes not previously reported. Our work illustrates the successful use of classical mechanics to describe all moving particles in C60, an approach that scales well to larger systems, for example, biomolecules. Comparisons of the model with experimental data on C60 ion fragmentation show excellent agreement under a variety of laser conditions. The results indicate that this modelling is applicable for X-ray interactions with any extended system, even at higher X-ray dose rates expected with future light sources.
Collapse
Affiliation(s)
- B F Murphy
- 1] Department of Physics, Western Michigan University, Kalamazoo, Michigan 49008, USA [2]
| | - T Osipov
- 1] Department of Physics, Western Michigan University, Kalamazoo, Michigan 49008, USA [2]
| | - Z Jurek
- 1] Center for Free-Electron Laser Science, DESY, 22607 Hamburg, Germany [2] The Hamburg Centre for Ultrafast Imaging, 22761 Hamburg, Germany [3]
| | - L Fang
- Department of Physics, Western Michigan University, Kalamazoo, Michigan 49008, USA
| | - S-K Son
- 1] Center for Free-Electron Laser Science, DESY, 22607 Hamburg, Germany [2] The Hamburg Centre for Ultrafast Imaging, 22761 Hamburg, Germany
| | - M Mucke
- Gothenburg University, Department of Physics Origovägen 6, SE-412 96 Gothenburg, Sweden
| | - J H D Eland
- 1] Gothenburg University, Department of Physics Origovägen 6, SE-412 96 Gothenburg, Sweden [2] Department of Chemistry, Oxford University, Oxford OX1 3QZ, UK
| | - V Zhaunerchyk
- Gothenburg University, Department of Physics Origovägen 6, SE-412 96 Gothenburg, Sweden
| | - R Feifel
- Gothenburg University, Department of Physics Origovägen 6, SE-412 96 Gothenburg, Sweden
| | - L Avaldi
- Instituto di Metodologie Inorganiche e dei Plasmi, C.N.R., Rome 00133, Italy
| | - P Bolognesi
- Instituto di Metodologie Inorganiche e dei Plasmi, C.N.R., Rome 00133, Italy
| | - C Bostedt
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - J D Bozek
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - J Grilj
- PULSE, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - M Guehr
- PULSE, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - L J Frasinski
- Blackett Laboratory, Imperial College London, London SW7 2AZ, UK
| | - J Glownia
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - D T Ha
- Department of Physics, University of Turku, FIN-20014 Turku, Finland
| | - K Hoffmann
- Department of Physics, University of Texas at Austin, Austin, Texas 78712, USA
| | - E Kukk
- Department of Physics, University of Turku, FIN-20014 Turku, Finland
| | - B K McFarland
- PULSE, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - C Miron
- Synchrotron SOLEIL, l'Orme des Merisiers, Saint-Aubin, BP 48, 91192 Gif-sur-Yvette, France
| | - E Sistrunk
- PULSE, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - R J Squibb
- 1] Gothenburg University, Department of Physics Origovägen 6, SE-412 96 Gothenburg, Sweden [2] Blackett Laboratory, Imperial College London, London SW7 2AZ, UK
| | - K Ueda
- Department of Physics, Tohoku University, Sendai 980-8577, Japan
| | - R Santra
- 1] Center for Free-Electron Laser Science, DESY, 22607 Hamburg, Germany [2] The Hamburg Centre for Ultrafast Imaging, 22761 Hamburg, Germany [3] Department of Physics, University of Hamburg, 20355 Hamburg, Germany
| | - N Berrah
- Department of Physics, University of Connecticut, Storrs, Connecticut 06269, USA
| |
Collapse
|
7
|
Huu NB, Denner EB, Ha DT, Wanner G, Stan-Lotter H. Marinobacter aquaeolei sp. nov., a halophilic bacterium isolated from a Vietnamese oil-producing well. Int J Syst Bacteriol 1999; 49 Pt 2:367-75. [PMID: 10319457 DOI: 10.1099/00207713-49-2-367] [Citation(s) in RCA: 171] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Several strains of moderately halophilic and mesophilic bacteria were isolated at the head of an oil-producing well on an offshore platform in southern Vietnam. Cells were Gram-negative, non-spore-forming, rod-shaped and motile by means of a polar flagellum. Growth occurred at NaCl concentrations between 0 and 20%; the optimum was 5% NaCl. One strain, which was designated VT8T, could degrade n-hexadecane, pristane and some crude oil components. It grew anaerobically in the presence of nitrate on succinate, citrate or acetate, but not on glucose. Several organic acids and amino acids were utilized as sole carbon and energy sources. The major components of its cellular fatty acids were C12:0 3-OH, C16:1, omega 9c, C16:0 and C18:1 omega 9c. The DNA G + C content was 55.7 mol%. 16S rDNA sequence analysis indicated that strain VT8T was closely related to Marinobacter sp. strain CAB (99.8% similarity) and Marinobaster hydrocarbonoclasticus (99.4% similarity). Its antibiotic resistance, isoprenoid quinones and fatty acids were similar to those of Marinobacter hydrocarbonoclasticus and Pseudomonas nautica. However, the whole-cell protein pattern of VT8T differed from that of other halophilic marine isolates, including P. nautica. DNA-DNA hybridization indicated that the level of relatedness to Marinobacter hydrocarbonoclasticus was 65% and that to P. nautica was 75%. Further differences were apparent in Fourier-transformed IR spectra of cells and lipopolysaccharide composition. It is proposed that VT8T should be the type strain of a new species and should be named Marinobacter aquaeolei. P. nautica may have been misclassified, as suggested previously, and may also belong to the genus Marinobacter.
Collapse
Affiliation(s)
- N B Huu
- Institute of Biotechnology, National Center for Natural Science and Technology, Tu liem, Hanoi, Vietnam
| | | | | | | | | |
Collapse
|
8
|
Huy NQ, Jin S, Amada K, Haruki M, Huu NB, Hang DT, Ha DT, Imanaka T, Morikawa M, Kanaya S. Characterization of petroleum-degrading bacteria from oil-contaminated sites in Vietnam. J Biosci Bioeng 1999; 88:100-2. [PMID: 16232582 DOI: 10.1016/s1389-1723(99)80184-4] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/1999] [Accepted: 04/14/1999] [Indexed: 11/17/2022]
Abstract
Four petroleum-degrading bacterial strains, 2TN-NB, 6TBX-CL, MVK2-5, and XCK, were isolated from various oil-contaminated sites in Vietnam. Determination of the nucleotide sequence of the gene encoding 16S rRNA allowed 2TN-NB to be identified as Acinetobacter sp. and the other three stains as Pseudomonas sp. Among the four isolates, 2TN-NB was most effective in degrading crude oil: in 1 d, it degraded 95% of the crude oil in the culture medium (5%, v/v). The isolated strains could also degrade a sulfur-containing aromatic hydrocarbon, dibenzothiophene (DBT), with low efficiency. Except for MVK2-5, which degraded crude oil least efficiently, the isolates produced biosurfactants in amounts sufficient for structural analysis. FT-IR measurement suggested that strains 6TBX-CL and XCK produced glycolipid-type biosurfactants while that produced by 2TN-NB was of the polysaccharide type.
Collapse
Affiliation(s)
- N Q Huy
- Institute of Biotechnology, Nghia Do, Cau Giay-Hanoi, Vietnam
| | | | | | | | | | | | | | | | | | | |
Collapse
|
9
|
Bögre L, Jonak C, Mink M, Meskiene I, Traas J, Ha DT, Swoboda I, Plank C, Wagner E, Heberle-Bors E, Hirt H. Developmental and cell cycle regulation of alfalfa nucMs1, a plant homolog of the yeast Nsr1 and mammalian nucleolin. Plant Cell 1996; 8:417-28. [PMID: 8721748 PMCID: PMC161110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
We report here the isolation and characterization of the nucMs1 alfalfa cDNA, whose predicted amino acid sequence structurally resembles the yeast Nsr1 protein and animal nucleolins. These proteins consist of an N-terminal acidic domain, centrally located RNA recognition motifs (RRMs), and a C-terminal glycine- and arginine-rich domain. In comparison with animal nucleolins that contain four RRMs, NucMs1 more closely resembles the yeast Nsr1 protein, which contains only two RRMs. A NucMs1 C-terminal peptide antibody specifically recognized a 95-kD nucleolar protein in alfalfa cells that changed its localization in a cell cycle-dependent manner. The nucMs1 transcript and p95nucMs1 protein levels correlated with cell proliferation, and nucMs1 gene expression was found to be induced in the G1 phase upon mitogenic stimulation of G0-arrested leaf cells. In situ hybridization analysis of different alfalfa organs during various developmental stages showed that nucMs1 gene expression is highest in root meristematic cells, but it is also found in other meristematic cells of the plant body. nucMs1 expression is tightly linked to cell proliferation but does not depend on a particular cell cycle phase. No nucMs1 expression was observed in cells that had exited the cell cycle and were undergoing differentiation or polar growth, indicating that nucMs1 may not be necessary for processes other than cell proliferation.
Collapse
Affiliation(s)
- L Bögre
- Institute of Microbiology and Genetics, University of Vienna, Austria
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
10
|
Dahl M, Meskiene I, Bögre L, Ha DT, Swoboda I, Hubmann R, Hirt H, Heberle-Bors E. The D-type alfalfa cyclin gene cycMs4 complements G1 cyclin-deficient yeast and is induced in the G1 phase of the cell cycle. Plant Cell 1995; 7:1847-57. [PMID: 8535138 PMCID: PMC161043 DOI: 10.1105/tpc.7.11.1847] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Cyclins are key regulators of the cell cycle in all eukaryotes. In alfalfa, we have previously isolated three B-type cyclins. The closely related cycMs1 and cycMs2 genes are expressed primarily during the G2 and M phases and are most likely mitotic cyclins; expression of the cycMs3 gene is induced in the G0-to-G1 transition, when cells reenter the cell cycle. By complementation of G1 cyclin-deficient yeast cells, a novel alfalfa cyclin, designated cycMs4, was isolated. The predicted amino acid sequence of the cycMs4 gene is most similar to that of the Arabidopsis cyclin delta 3 gene. CycMs4 and cyclin delta 3 belong to the class of D-type cyclins and contain PEST-rich regions and a retinoblastoma binding motif. When comparing expression levels in different organs, cycMs4 transcripts were present predominantly in roots. Whereas expression of the cycMs4 gene was cell cycle-regulated in suspension-cultured cells, transcription in roots was observed to depend also on the positional context of the cell. When differentiated G0-arrested leaf cells were induced to resume cell division by treatment with plant hormones, cycMs4 transcription was induced before the onset of DNA synthesis. Whereas this induction was preceded by that of the cycMs3 gene, cycMs2 expression occurred later and at the same time as mitotic activity. These data suggest that cycMs4 plays a role in the G1-to-S transition and provide a model to investigate the plant cell cycle at the molecular level.
Collapse
Affiliation(s)
- M Dahl
- Institute of Microbiology and Genetics, Vienna Biocenter, Austria
| | | | | | | | | | | | | | | |
Collapse
|
11
|
Meskiene I, Bögre L, Dahl M, Pirck M, Ha DT, Swoboda I, Heberle-Bors E, Ammerer G, Hirt H. cycMs3, a novel B-type alfalfa cyclin gene, is induced in the G0-to-G1 transition of the cell cycle. Plant Cell 1995; 7:759-71. [PMID: 7647566 PMCID: PMC160829 DOI: 10.1105/tpc.7.6.759] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Cyclins are key regulators of the cell cycle in all eukaryotes. We have previously isolated two B-type cyclin genes, cycMs1 and cycMs2, from alfalfa that are primarily expressed during the G2-to-M phase transition and are most likely mitotic cyclin genes. Here, we report the isolation of a novel alfalfa cyclin gene, termed cycMs3 (for cyclin Medicago sativa), by selecting for mating type alpha-pheromone-induced cell cycle arrest suppression in yeast. The central region of the predicted amino acid sequence of the cycMs3 gene is most similar to the cyclin box of yeast B-type and mammalian A- and B-type cyclins. In situ hybridization showed that cycMs3 mRNA can be detected only in proliferating cells and not in differentiated alfalfa cells. When differentiated G0-arrested cells were induced to reenter the cell cycle in the G1 phase and resume cell division by treatment with plant hormones, cycMs3 transcript levels increased long before the onset of DNA synthesis. In contrast, histone H3-1 mRNA and cycMs2 transcripts were not observed before DNA replication and mitosis, respectively. In addition, cycMs3 mRNA was found in all stages of the cell cycle in synchronously dividing cells, whereas the cycMs2 and histone H3-1 genes showed a G2-to-M phase- or S phase-specific transcription pattern, respectively. These data suggest that the role of cyclin CycMs3 differs from that of CycMs1 and CycMs2. We propose that CycMs3 helps control reentry of quiescent G0-arrested cells into the G1 phase of the cell cycle.
Collapse
Affiliation(s)
- I Meskiene
- Vienna Biocenter, Institute of Microbiology and Genetics, Austria
| | | | | | | | | | | | | | | | | |
Collapse
|
12
|
Putnoky P, Petrovics G, Kereszt A, Grosskopf E, Ha DT, Bánfalvi Z, Kondorosi A. Rhizobium meliloti lipopolysaccharide and exopolysaccharide can have the same function in the plant-bacterium interaction. J Bacteriol 1990; 172:5450-8. [PMID: 2168384 PMCID: PMC213212 DOI: 10.1128/jb.172.9.5450-5458.1990] [Citation(s) in RCA: 57] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
A fix region of Rhizobium meliloti 41 involved both in symbiotic nodule development and in the adsorption of bacteriophage 16-3 was delimited by directed Tn5 mutagenesis. Mutations in this DNA region were assigned to four complementation units and were mapped close to the pyr-2 and pyr-29 chromosomal markers. Phage inactivation studies with bacterial cell envelope preparations and crude lipopolysaccharides (LPS) as well as preliminary characterization of LPS in the mutants indicated that these genes are involved in the synthesis of a strain-specific LPS. Mutations in this DNA region resulted in a Fix- phenotype in AK631, an exopolysaccharide (EPS)-deficient derivative of R. meliloti 41; however, they did not influence the symbiotic efficiency of the parent strain. An exo region able to restore the EPS production of AK631 was isolated and shown to be homologous to the exoB region of R. meliloti SU47. By generating double mutants, we demonstrated that exo and lps genes determine similar functions in the course of nodule development, suggesting that EPS and LPS may provide equivalent information for the host plant.
Collapse
Affiliation(s)
- P Putnoky
- Institute of Genetics, Biological Research Center, Hungarian Academy of Sciences, Szeged
| | | | | | | | | | | | | |
Collapse
|
13
|
Abstract
To identify bacterial genes involved in symbiotic nodule development, ineffective nodules of alfalfa (Medicago sativa) induced by 64 different Fix-mutants of Rhizobium meliloti were characterized by assaying for symbiotic gene expression and by morphological studies. The expression of leghemoglobin and nodulin-25 genes from alfalfa and of the nifHD genes from R. meliloti were monitored by hybridizing the appropriate DNA probes to RNA samples prepared from nodules. The mutants were accordingly divided into three groups. In group I none of the genes were expressed, in group II only the plant genes were expressed and in group III all three genes were transcribed. Light and electron microscopical analysis of nodules revealed that nodule development was halted at different stages in nodules induced by different group I mutants. In most cases nodules were empty lacking infection threads and bacteroids or nodules contained infection threads and a few released bacteroids. In nodules induced by a third mutant class bacteria were released into the host cells, however the formation of the peribacteroid membrane was not normal. On this basis we suggest that peribacteroid membrane formation precedes leghemoglobin and nodulin-25 induction, moreover, after induction of nodulation by the nod genes at least two communication steps between the bacteria and the host plants are necessary for the development of the mature nodule. By complementing each mutant of group I with a genomic R. meliloti library made in pLAFRl, four new fix loci were identified, indicating that several bacterial genes are involved in late nodule development.
Collapse
Affiliation(s)
- P Putnoky
- Institute of Genetics, Hungarian Academy of Sciences, Szeged
| | | | | | | | | |
Collapse
|