1
|
Thakur P, Gopalakrishnan V, Saxena P, Subramaniam M, Goh KM, Peyton B, Fields M, Sani RK. Influence of Copper on Oleidesulfovibrio alaskensis G20 Biofilm Formation. Microorganisms 2024; 12:1747. [PMID: 39338422 PMCID: PMC11434458 DOI: 10.3390/microorganisms12091747] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2024] [Revised: 08/19/2024] [Accepted: 08/20/2024] [Indexed: 09/30/2024] Open
Abstract
Copper is known to have toxic effects on bacterial growth. This study aimed to determine the influence of copper ions on Oleidesulfovibrio alaskensis G20 biofilm formation in a lactate-C medium supplemented with variable copper ion concentrations. OA G20, when grown in media supplemented with high copper ion concentrations of 5, 15, and 30 µM, exhibited inhibited growth in its planktonic state. Conversely, under similar copper concentrations, OA G20 demonstrated enhanced biofilm formation on glass coupons. Microscopic studies revealed that biofilms exposed to copper stress demonstrated a change in cellular morphology and more accumulation of carbohydrates and proteins than controls. Consistent with these findings, sulfur (dsrA, dsrB, sat, aprA) and electron transport (NiFeSe, NiFe, ldh, cyt3) genes, polysaccharide synthesis (poI), and genes involved in stress response (sodB) were significantly upregulated in copper-induced biofilms, while genes (ftsZ, ftsA, ftsQ) related to cellular division were negatively regulated compared to controls. These results indicate that the presence of copper ions triggers alterations in cellular morphology and gene expression levels in OA G20, impacting cell attachment and EPS production. This adaptation, characterized by increased biofilm formation, represents a crucial strategy employed by OA G20 to resist metal ion stress.
Collapse
Affiliation(s)
- Payal Thakur
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City, SD 57701, USA
- 2-Dimensional Materials for Biofilm Engineering, Science and Technology, South Dakota School of Mines and Technology, Rapid City, SD 57701, USA
- Data Driven Material Discovery Center for Bioengineering Innovation, South Dakota School of Mines and Technology, Rapid City, SD 57701, USA
| | - Vinoj Gopalakrishnan
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City, SD 57701, USA
- 2-Dimensional Materials for Biofilm Engineering, Science and Technology, South Dakota School of Mines and Technology, Rapid City, SD 57701, USA
- Data Driven Material Discovery Center for Bioengineering Innovation, South Dakota School of Mines and Technology, Rapid City, SD 57701, USA
| | - Priya Saxena
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City, SD 57701, USA
- 2-Dimensional Materials for Biofilm Engineering, Science and Technology, South Dakota School of Mines and Technology, Rapid City, SD 57701, USA
- Data Driven Material Discovery Center for Bioengineering Innovation, South Dakota School of Mines and Technology, Rapid City, SD 57701, USA
| | | | - Kian Mau Goh
- Faculty of Science, Universiti Teknologi Malaysia, Johor Bahru 81310, Malaysia
| | - Brent Peyton
- Department of Chemical and Biological Engineering, Montana State University, Bozeman, MT 59717, USA
| | - Matthew Fields
- Department of Chemical and Biological Engineering, Montana State University, Bozeman, MT 59717, USA
| | - Rajesh Kumar Sani
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City, SD 57701, USA
- 2-Dimensional Materials for Biofilm Engineering, Science and Technology, South Dakota School of Mines and Technology, Rapid City, SD 57701, USA
- Data Driven Material Discovery Center for Bioengineering Innovation, South Dakota School of Mines and Technology, Rapid City, SD 57701, USA
- BuG ReMeDEE Consortium, South Dakota School of Mines and Technology, Rapid City, SD 57701, USA
- Composite and Nanocomposite Advanced Manufacturing Centre-Biomaterials, Rapid City, SD 57701, USA
| |
Collapse
|
2
|
Guo X, Qi Z, Li J, Tong H, Ren N, You S. Overlooked volcanic effect during transmission of antibiotic resistance genes induced by copper and zinc. CHEMOSPHERE 2024; 362:142713. [PMID: 38944351 DOI: 10.1016/j.chemosphere.2024.142713] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2024] [Revised: 06/22/2024] [Accepted: 06/26/2024] [Indexed: 07/01/2024]
Abstract
Adding heavy metals such as copper and zinc to animal feeds is common practice to promote growth, but meanwhile has side consequence of enhancing spread of antibiotic resistance genes (ARGs) in soil. This presents a global challenge to food security and human health. We in this study investigated the transmission of typical ARGs, i. e. β-lactamase genes (β-RGs), in dairy farm environments where dietary Cu and Zn were present in a wide range of concentration. The β-RGs were demonstrated to be highly prevalent across environmental media, with a relative abundance of 94.55%, dominated by mechanisms of antibiotic deactivation (93.75%) and cellular protection (6.25%). More importantly, we first found the transmission of ARGs to be highly dependent on the overlooked volcanic effect, i. e. low-concentration Cu (12-22 mg/kg) and Zn (45-80 mg/kg) acted as micronutrients necessary for microbial growth but facilitated ARGs transfer, whereas higher-concentration Cu (22-39 mg/kg) and Zn (80-153 mg/kg) became toxic to microbial communities and gene expression patterns. Notably, the specific microbial phyla Proteobacteria (2.28-82.94%), Bacteroidetes (0.02-56.48%) and Actinobacteria (1.62-12.92%) exhibited resistance at low concentration of Cu and Zn, which enhanced the transmission of β-RGs. However, this process was inhibited at higher concentration due to inactivation of microbes by Cu and Zn. The increase in resistance was first observed in class Gammaproteobacteria (2.02-88.51%) and Alphaproteobacteria (0.68-10.1%) with increased Cu and Zn concentration. This resulted in heightened transfer of ARGs by tnpA-07 (80.35%) due to protection of thicker cell membrane by chelation with Cu and Zn. This study not only offers mechanistic insights into the volcanic effect of dietary metals on dissemination of ARGs, but also has important implications for safe management of agricultural settings.
Collapse
Affiliation(s)
- Xiaorui Guo
- Engineering Research Center for Medicine, Ministry of Education, Harbin University of Commerce, Harbin, 150076, PR China; School of Food Engineering, Harbin University of Commerce, Harbin, 150028, PR China
| | - Zheng Qi
- Engineering Research Center for Medicine, Ministry of Education, Harbin University of Commerce, Harbin, 150076, PR China.
| | - Junsheng Li
- School of Food Engineering, Harbin University of Commerce, Harbin, 150028, PR China
| | - Hailong Tong
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, PR China
| | - Nanqi Ren
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, PR China
| | - Shijie You
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, PR China.
| |
Collapse
|
3
|
Ferreira MV, Naranjo E, Denis N, Cobine P, De La Fuente L, Siri MI. Calcium modulation of bacterial wilt disease on potato. Appl Environ Microbiol 2024; 90:e0024224. [PMID: 38690890 PMCID: PMC11107177 DOI: 10.1128/aem.00242-24] [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: 02/19/2024] [Accepted: 03/22/2024] [Indexed: 05/03/2024] Open
Abstract
Ralstonia solanacearum species complex (RSSC) is a phytopathogenic bacterial group that causes bacterial wilt in several crops, being potato (Solanum tuberosum) one of the most important hosts. The relationship between the potato plant ionome (mineral and trace elements composition) and the resistance levels to this pathogen has not been addressed until now. Mineral content of xylem sap, roots, stems and leaves of potato genotypes with different levels of resistance to bacterial wilt was assessed in this work, revealing a positive correlation between divalent calcium (Ca) cation concentrations and genotype resistance. The aim of this study was to investigate the effect of Ca on bacterial wilt resistance, and on the growth and virulence of RSSC. Ca supplementation significantly decreased the growth rate of Ralstonia pseudosolanacearum GMI1000 in minimal medium and affected several virulence traits such as biofilm formation and twitching motility. We also incorporate for the first time the use of microfluidic chambers to follow the pathogen growth and biofilm formation in conditions mimicking the plant vascular system. By using this approach, a reduction in biofilm formation was observed when both, rich and minimal media, were supplemented with Ca. Assessment of the effect of Ca amendments on bacterial wilt progress in potato genotypes revealed a significant delay in disease progress, or a complete absence of wilting symptoms in the case of partially resistant genotypes. This work contributes to the understanding of Ca effect on virulence of this important pathogen and provides new strategies for an integrated control of bacterial wilt on potato. IMPORTANCE Ralstonia solanacearum species complex (RSSC) includes a diverse group of bacterial strains that cause bacterial wilt. This disease is difficult to control due to pathogen aggressiveness, persistence, wide range of hosts, and wide geographic distribution in tropical, subtropical, and temperate regions. RSSC causes considerable losses depending on the pathogen strain, host, soil type, environmental conditions, and cultural practices. In potato, losses of $19 billion per year have been estimated for this pathogen worldwide. In this study, we report for the first time the mineral composition found in xylem sap and plant tissues of potato germplasm with different levels of resistance to bacterial wilt. This study underscores the crucial role of calcium (Ca) concentration in the xylem sap and stem in relation to the resistance of different genotypes. Our in vitro experiments provide evidence of Ca's inhibitory effect on the growth, biofilm formation, and twitching movement of the model RSSC strain R. pseudosolanacearum GMI1000. This study introduces a novel element, the Ca concentration, which should be included into the integrated disease control management strategies for bacterial wilt in potatoes.
Collapse
Affiliation(s)
- María Virginia Ferreira
- Área Microbiología, Departamento de Biociencias, Facultad de Química, Universidad de la República, Montevideo, Uruguay
| | - Eber Naranjo
- Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama, USA
| | - Nicol Denis
- Área Microbiología, Departamento de Biociencias, Facultad de Química, Universidad de la República, Montevideo, Uruguay
| | - Paul Cobine
- Department of Biological Sciences, Auburn University, Auburn, Alabama, USA
| | - Leonardo De La Fuente
- Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama, USA
| | - María Inés Siri
- Área Microbiología, Departamento de Biociencias, Facultad de Química, Universidad de la República, Montevideo, Uruguay
| |
Collapse
|
4
|
De La Fuente L, Navas-Cortés JA, Landa BB. Ten Challenges to Understanding and Managing the Insect-Transmitted, Xylem-Limited Bacterial Pathogen Xylella fastidiosa. PHYTOPATHOLOGY 2024; 114:869-884. [PMID: 38557216 DOI: 10.1094/phyto-12-23-0476-kc] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
An unprecedented plant health emergency in olives has been registered over the last decade in Italy, arguably more severe than what occurred repeatedly in grapes in the United States in the last 140 years. These emergencies are epidemics caused by a stealthy pathogen, the xylem-limited, insect-transmitted bacterium Xylella fastidiosa. Although these epidemics spurred research that answered many questions about the biology and management of this pathogen, many gaps in knowledge remain. For this review, we set out to represent both the U.S. and European perspectives on the most pressing challenges that need to be addressed. These are presented in 10 sections that we hope will stimulate discussion and interdisciplinary research. We reviewed intrinsic problems that arise from the fastidious growth of X. fastidiosa, the lack of specificity for insect transmission, and the economic and social importance of perennial mature woody plant hosts. Epidemiological models and predictions of pathogen establishment and disease expansion, vital for preparedness, are based on very limited data. Most of the current knowledge has been gathered from a few pathosystems, whereas several hundred remain to be studied, probably including those that will become the center of the next epidemic. Unfortunately, aspects of a particular pathosystem are not always transferable to others. We recommend diversification of research topics of both fundamental and applied nature addressing multiple pathosystems. Increasing preparedness through knowledge acquisition is the best strategy to anticipate and manage diseases caused by this pathogen, described as "the most dangerous plant bacterium known worldwide."
Collapse
Affiliation(s)
- Leonardo De La Fuente
- Department of Entomology and Plant Pathology, Auburn University, Auburn, AL 36849, U.S.A
| | - Juan A Navas-Cortés
- Department of Crop Protection. Institute for Sustainable Agriculture (IAS), Consejo Superior de Investigaciones Científicas (CSIC), Córdoba, Spain
| | - Blanca B Landa
- Department of Crop Protection. Institute for Sustainable Agriculture (IAS), Consejo Superior de Investigaciones Científicas (CSIC), Córdoba, Spain
| |
Collapse
|
5
|
Bleve G, Trivellin N, Chirizzi D, Tarantini A, Orlandi VT, Milano F. Sensitivity of Xylella fastidiosa subsp. pauca Salento-1 to light at 410 nm. Photochem Photobiol Sci 2024; 23:793-801. [PMID: 38578539 DOI: 10.1007/s43630-024-00556-z] [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: 11/07/2023] [Accepted: 02/14/2024] [Indexed: 04/06/2024]
Abstract
All over the world, from America to the Mediterranean Sea, the plant pathogen Xylella fastidiosa represents one of the most difficult challenges with many implications at ecological, agricultural, and economic levels. X. fastidiosa is a rod-shaped Gram-negative bacterium belonging to the family of Xanthomonadaceae. It grows at very low rates and infects a wide range of plants thanks to different vectors. Insects, through their stylets, suck a sap rich in nutrients and inject bacteria into xylem vessels. Since, until now, no antimicrobial treatment has been successfully applied to kill X. fastidiosa and/or prevent its diffusion, in this study, antimicrobial blue light (aBL) was explored as a potential anti-Xylella tool. Xylella fastidiosa subsp. pauca Salento-1, chosen as a model strain, showed a certain degree of sensitivity to light at 410 nm. The killing effect was light dose dependent and bacterial concentration dependent. These preliminary results support the potential of blue light in decontamination of agricultural equipment and/or plant surface; however, further investigations are needed for in vivo applications.
Collapse
Affiliation(s)
- Gianluca Bleve
- Istituto di Scienze delle Produzioni Alimentari (ISPA), Consiglio Nazionale delle Ricerche (CNR), SP Lecce-Monteroni, 73100, Lecce, Italy
| | - Nicola Trivellin
- Department of Industrial Engineering, University of Padua, via Venezia, 1, 35131, Padova, Italy
| | - Daniela Chirizzi
- Istituto Zooprofilattico Sperimentale della Puglia e della Basilicata, via Manfredonia 20, 71100, Foggia, Italy
| | - Annamaria Tarantini
- Istituto di Scienze delle Produzioni Alimentari (ISPA), Consiglio Nazionale delle Ricerche (CNR), SP Lecce-Monteroni, 73100, Lecce, Italy
- Dipartimento di Scienze del Suolo, della Pianta e degli Alimenti (Di.S.S.P.A), Università di Bari, via G. Amendola, 165/A, Bari, 70126, Italy
| | - Viviana Teresa Orlandi
- Departemnt of Biotechnologies and Life Sciences, University of Insubria, via J. H. Dunant, 3, 21100, Varese, Italy.
| | - Francesco Milano
- Istituto di Scienze delle Produzioni Alimentari (ISPA), Consiglio Nazionale delle Ricerche (CNR), SP Lecce-Monteroni, 73100, Lecce, Italy
| |
Collapse
|
6
|
Yang Y, Zhang Q, Lin Q, Sun F, Shen C, Lin H, Su X. Unveiling the PCB biodegradation potential and stress survival strategies of resuscitated strain Pseudomonas sp. HR1. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 344:123320. [PMID: 38185359 DOI: 10.1016/j.envpol.2024.123320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2023] [Revised: 01/03/2024] [Accepted: 01/04/2024] [Indexed: 01/09/2024]
Abstract
The exploration of resuscitated strains, facilitated by the resuscitation promoting factor (Rpf), has substantially expanded the pool of cultivated degraders, enhancing the screening of bio-inoculants for bioremediation applications. However, it remains unknown whether these resuscitated strains can re-enter the viable but non-culturable (VBNC) state and the specific stress conditions that trigger such a transition. In this work, the whole genome, and polychlorinated biphenyl (PCB)-degrading capabilities of a resuscitated strain HR1, were investigated. Notably, the focus of this exploration was on elucidating whether HR1 would undergo a transition into the VBNC state when exposed to low temperature and PCBs, with and without the presence of heavy metals (HMs). The results suggested that the resuscitated strain Pseudomonas sp. HR1 harbored various functional genes related to xenobiotic biodegradation, demonstrating remarkable efficiency in Aroclor 1242 degradation and strong resistance against stress induced by low temperature and PCBs. Nevertheless, when exposed to the combined stress of low temperature, PCBs, and HMs, HR1 underwent a transition into the VBNC state. This transition was characterized by significant decreases in enzyme activities and notable changes in both morphological and physiological traits when compared to normal cells. Gene expression analysis revealed molecular shifts underlying the VBNC state, with down-regulated genes showed differential expression across multiple pathways and functions, including oxidative phosphorylation, glycolysis, tricarboxylic acid cycle, amino acid metabolism, translation and cytoplasm, while up-regulated genes predominantly associated with transcription regulation, membrane function, quorum sensing, and transporter activity. These findings highlighted the great potential of resuscitated strains as bio-inoculants in bioaugmentation and shed light on the survival mechanisms of functional strains under stressful conditions, which should be carefully considered during bioremediation processes.
Collapse
Affiliation(s)
- Yingying Yang
- College of Geography and Environmental Science, Zhejiang Normal University, Jinhua, 321004, China
| | - Qian Zhang
- College of Geography and Environmental Science, Zhejiang Normal University, Jinhua, 321004, China
| | - Qihua Lin
- College of Geography and Environmental Science, Zhejiang Normal University, Jinhua, 321004, China
| | - Faqian Sun
- College of Geography and Environmental Science, Zhejiang Normal University, Jinhua, 321004, China
| | - Chaofeng Shen
- Department of Environmental Engineering, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Hongjun Lin
- College of Geography and Environmental Science, Zhejiang Normal University, Jinhua, 321004, China
| | - Xiaomei Su
- College of Geography and Environmental Science, Zhejiang Normal University, Jinhua, 321004, China.
| |
Collapse
|
7
|
Hussain M, Girelli CR, Verweire D, Oehl MC, Avendaño MS, Scortichini M, Fanizzi FP. 1H-NMR Metabolomics Study after Foliar and Endo-Therapy Treatments of Xylella fastidiosa subsp. pauca Infected Olive Trees: Medium Time Monitoring of Field Experiments. PLANTS (BASEL, SWITZERLAND) 2023; 12:1946. [PMID: 37653863 PMCID: PMC10221468 DOI: 10.3390/plants12101946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Revised: 04/30/2023] [Accepted: 05/05/2023] [Indexed: 09/02/2023]
Abstract
Here we report the medium-term effects of foliar spray and endo-therapy treatments with different doses of a Cu/Zn citric acid biocomplex (Dentamet®) in Xylella fastidiosa infected olive trees of Salento, Apulia region (South-east Italy). Leaf extract samples from field-treated 150 years old olive trees cvs Ogliarola salentina and Cellina di Nardò were studied by 1H NMR-based metabolomics. The result of different applications of Dentamet® endo-therapy after 60, 120 and 180 days in comparison with traditional foliar spray treatment and water injection as a control have been investigated. The metabolic profile analyses, performed by 1H NMR-based metabolomic approach, indicated plant metabolites variations connected to the disease progression such as mannitol, quinic acid, and oleuropein related compounds. The best results, in terms of discrimination of the metabolic profiles with respect to water injection, were found for monthly endo-therapy treatments. Dentamet® foliar application demonstrated more specific time related progressive effectiveness with respect to intravascular treatments. Therefore, besides a possible more effective performance of endo-therapy with respect to foliar treatments, the need of further doses/frequencies trimming to obtain long-term results was also assessed. The present field studies confirmed the indication of Dentamet® effectiveness in metabolic variation induction, potentially linked with reducing the X. fastidiosa subspecies pauca related Olive Quick Decline Syndrome (OQDS) symptoms development.
Collapse
Affiliation(s)
- Mudassar Hussain
- Department of Biological and Environmental Sciences and Technologies, University of Salento, Prov.le Lecce-Monteroni, 73100 Lecce, Italy;
| | - Chiara Roberta Girelli
- Department of Biological and Environmental Sciences and Technologies, University of Salento, Prov.le Lecce-Monteroni, 73100 Lecce, Italy;
| | - Dimitri Verweire
- Invaio Sciences, Cambridge, MA 02138, USA; (D.V.); (M.C.O.); (M.S.A.)
| | - Michael C. Oehl
- Invaio Sciences, Cambridge, MA 02138, USA; (D.V.); (M.C.O.); (M.S.A.)
| | - Maier S. Avendaño
- Invaio Sciences, Cambridge, MA 02138, USA; (D.V.); (M.C.O.); (M.S.A.)
| | - Marco Scortichini
- Council for Agricultural Research and Agricultural Economic Analyses (CREA), Research Centre for Olive, Fruit and Citrus Crops, Via di Fioranello, 52, 00134 Roma, Italy;
| | - Francesco Paolo Fanizzi
- Department of Biological and Environmental Sciences and Technologies, University of Salento, Prov.le Lecce-Monteroni, 73100 Lecce, Italy;
| |
Collapse
|
8
|
Bai K, Xu X, Wang X, Li Y, Yu C, Jiang N, Li J, Luo L. Transcriptional profiling of Xanthomonas campestris pv. campestris in viable but nonculturable state. BMC Genomics 2023; 24:105. [PMID: 36894875 PMCID: PMC9999588 DOI: 10.1186/s12864-023-09200-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Accepted: 02/21/2023] [Indexed: 03/11/2023] Open
Abstract
BACKGROUND Xanthomonas campestris pv. campestris (Xcc) is an important seed-borne plant pathogenic bacteria that can cause a serious threat to cruciferous crops. Bacteria can enter into the viable but non-culturable (VBNC) state under stress conditions, and cause potential risks to agricultural production because the VBNC bacterial cells will evade culture-based detection. However, little is known about the mechanism of VBNC. Our previous study showed that Xcc could be induced into VBNC state by copper ion (Cu2+). RESULTS Here, RNA-seq was performed to explore the mechanism of VBNC state. The results indicated that expression profiling was changed dramatically in the different VBNC stages (0 d, 1 d, 2 d and 10 d). Moreover, metabolism related pathways were enriched according to COG, GO and KEGG analysis of differentially expressed genes (DEGs). The DEGs associated with cell motility were down-regulated, whereas pathogenicity related genes were up-regulated. This study revealed that the high expression of genes related to stress response could trigger the active cells to VBNC state, while the genes involved in transcription and translation category, as well as transport and metabolism category, were ascribed to maintaining the VBNC state. CONCLUSION This study summarized not only the related pathways that might trigger and maintain VBNC state, but also the expression profiling of genes in different survival state of bacteria under stress. It provided a new kind of gene expression profile and new ideas for studying VBNC state mechanism in X. campestris pv. campestris.
Collapse
Affiliation(s)
- Kaihong Bai
- School of Life Sciences, Zhengzhou University, Zhengzhou, Henan, 450001, People's Republic of China.,Department of Plant Pathology, Key Laboratory of Seed Disease Testing and Control, MOA Key Lab of Pest Monitoring and Green Management, China Agricultural University, No.2 Yuanmingyuan West Road, Haidian District, Beijing, 100193, People's Republic of China
| | - Xiaoli Xu
- Department of Plant Pathology, Key Laboratory of Seed Disease Testing and Control, MOA Key Lab of Pest Monitoring and Green Management, China Agricultural University, No.2 Yuanmingyuan West Road, Haidian District, Beijing, 100193, People's Republic of China
| | - Xudong Wang
- Department of Plant Pathology, Key Laboratory of Seed Disease Testing and Control, MOA Key Lab of Pest Monitoring and Green Management, China Agricultural University, No.2 Yuanmingyuan West Road, Haidian District, Beijing, 100193, People's Republic of China
| | - Yao Li
- Department of Plant Pathology, Key Laboratory of Seed Disease Testing and Control, MOA Key Lab of Pest Monitoring and Green Management, China Agricultural University, No.2 Yuanmingyuan West Road, Haidian District, Beijing, 100193, People's Republic of China
| | - Chengxuan Yu
- Department of Plant Pathology, Key Laboratory of Seed Disease Testing and Control, MOA Key Lab of Pest Monitoring and Green Management, China Agricultural University, No.2 Yuanmingyuan West Road, Haidian District, Beijing, 100193, People's Republic of China
| | - Na Jiang
- Department of Plant Pathology, Key Laboratory of Seed Disease Testing and Control, MOA Key Lab of Pest Monitoring and Green Management, China Agricultural University, No.2 Yuanmingyuan West Road, Haidian District, Beijing, 100193, People's Republic of China
| | - Jianqiang Li
- Department of Plant Pathology, Key Laboratory of Seed Disease Testing and Control, MOA Key Lab of Pest Monitoring and Green Management, China Agricultural University, No.2 Yuanmingyuan West Road, Haidian District, Beijing, 100193, People's Republic of China
| | - Laixin Luo
- Department of Plant Pathology, Key Laboratory of Seed Disease Testing and Control, MOA Key Lab of Pest Monitoring and Green Management, China Agricultural University, No.2 Yuanmingyuan West Road, Haidian District, Beijing, 100193, People's Republic of China.
| |
Collapse
|
9
|
De La Fuente L, Merfa MV, Cobine PA, Coleman JJ. Pathogen Adaptation to the Xylem Environment. ANNUAL REVIEW OF PHYTOPATHOLOGY 2022; 60:163-186. [PMID: 35472277 DOI: 10.1146/annurev-phyto-021021-041716] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
A group of aggressive pathogens have evolved to colonize the plant xylem. In this vascular tissue, where water and nutrients are transported from the roots to the rest of the plant, pathogens must be able to thrive under acropetal xylem sap flow and scarcity of nutrients while having direct contact only with predominantly dead cells. Nevertheless, a few bacteria have adapted to exclusively live in the xylem, and various pathogens may colonize other plant niches without causing symptoms unless they reach the xylem. Once established, the pathogens modulate its physicochemical conditions to enhance their growth and virulence. Adaptation to the restrictive lifestyle of the xylem leads to genome reduction in xylem-restricted bacteria, as they have a higher proportion of pseudogenes in their genome. The basis of xylem adaptation is not completely understood; therefore, a need still exists for model systems to advance the knowledge on this topic.
Collapse
Affiliation(s)
- Leonardo De La Fuente
- Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama, USA;
| | - Marcus V Merfa
- Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama, USA;
| | - Paul A Cobine
- Department of Biological Sciences, Auburn University, Auburn, Alabama, USA
| | - Jeffrey J Coleman
- Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama, USA;
| |
Collapse
|
10
|
The Role of RelA and SpoT on ppGpp Production, Stress Response, Growth Regulation, and Pathogenicity in Xanthomonas campestris pv. campestris. Microbiol Spectr 2021; 9:e0205721. [PMID: 34935430 PMCID: PMC8693919 DOI: 10.1128/spectrum.02057-21] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The alarmone ppGpp plays an important role in the survival of bacteria by triggering the stringent response when exposed to environmental stress. Although Xanthomonas campestris pv. campestris (Xcc), which causes black rot disease in crucifers, is a representative species of Gram-negative phytopathogenic bacteria, relatively little is known regarding the factors influencing the stringent response in this species. However, previous studies in other Gram-negative bacteria have indicated that RelA and SpoT play a critical role in ppGpp synthesis. The current study found that these proteins also had an important role in Xcc, with a ΔrelAΔspoT double mutant being unable to produce ppGpp, resulting in changes to phenotype including reduced production of exopolysaccharides (EPS), exoenzymes, and biofilm, as well the loss of swarming motility and pathogenicity. The ppGpp-deficient mutant also exhibited greater sensitivity to environment stress, being almost incapable of growth on modified minimal medium (mMM) and having a much greater propensity to enter the viable but nonculturable (VBNC) state in response to oligotrophic conditions (0.85% NaCl). These findings much advance our understanding of the role of ppGpp in the biology of Xcc and could have important implications for more effective management of this important pathogen. IMPORTANCEXanthomonas campestris pv. campestris (Xcc) is a typical seedborne phytopathogenic bacterium that causes large economic losses worldwide, and this is the first original research article to investigate the role of ppGpp in this important species. Here, we revealed the function of RelA and SpoT in ppGpp production, physiology, pathogenicity, and stress resistance in Xcc. Most intriguingly, we found that ppGpp levels and downstream ppGpp-dependent phenotypes were mediated predominantly by SpoT, with RelA having only a supplementary role. Taken together, the results of the current study provide new insight into the role of ppGpp in the biology of Xcc, which could also have important implications for the role of ppGpp in the survival and pathogenicity of other pathogenic bacteria.
Collapse
|
11
|
Moll L, Badosa E, Planas M, Feliu L, Montesinos E, Bonaterra A. Antimicrobial Peptides With Antibiofilm Activity Against Xylella fastidiosa. Front Microbiol 2021; 12:753874. [PMID: 34819923 PMCID: PMC8606745 DOI: 10.3389/fmicb.2021.753874] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Accepted: 10/04/2021] [Indexed: 11/26/2022] Open
Abstract
Xylella fastidiosa is a plant pathogen that was recently introduced in Europe and is causing havoc to its agriculture. This Gram-negative bacterium invades the host xylem, multiplies, and forms biofilm occluding the vessels and killing its host. In spite of the great research effort, there is no method that effectively prevents or cures hosts from infections. The main control strategies up to now are eradication, vector control, and pathogen-free plant material. Antimicrobial peptides have arisen as promising candidates to combat this bacterium due to their broad spectrum of activity and low environmental impact. In this work, peptides previously reported in the literature and newly designed analogs were studied for its bactericidal and antibiofilm activity against X. fastidiosa. Also, their hemolytic activity and effect on tobacco leaves when infiltrated were determined. To assess the activity of peptides, the strain IVIA 5387.2 with moderate growth, able to produce biofilm and susceptible to antimicrobial peptides, was selected among six representative strains found in the Mediterranean area (DD1, CFBP 8173, Temecula, IVIA 5387.2, IVIA 5770, and IVIA 5901.2). Two interesting groups of peptides were identified with bactericidal and/or antibiofilm activity and low-moderate toxicity. The peptides 1036 and RIJK2 with dual (bactericidal-antibiofilm) activity against the pathogen and moderate toxicity stand out as the best candidates to control X. fastidiosa diseases. Nevertheless, peptides with only antibiofilm activity and low toxicity are also promising agents as they could prevent the occlusion of xylem vessels caused by the pathogen. The present work contributes to provide novel compounds with antimicrobial and antibiofilm activity that could lead to the development of new treatments against diseases caused by X. fastidiosa.
Collapse
Affiliation(s)
- Luís Moll
- Laboratory of Plant Pathology, Institute of Food and Agricultural Technology-CIDSAV-XaRTA, University of Girona, Girona, Spain
| | - Esther Badosa
- Laboratory of Plant Pathology, Institute of Food and Agricultural Technology-CIDSAV-XaRTA, University of Girona, Girona, Spain
| | - Marta Planas
- LIPPSO, Department of Chemistry, University of Girona, Girona, Spain
| | - Lidia Feliu
- LIPPSO, Department of Chemistry, University of Girona, Girona, Spain
| | - Emilio Montesinos
- Laboratory of Plant Pathology, Institute of Food and Agricultural Technology-CIDSAV-XaRTA, University of Girona, Girona, Spain
| | - Anna Bonaterra
- Laboratory of Plant Pathology, Institute of Food and Agricultural Technology-CIDSAV-XaRTA, University of Girona, Girona, Spain
| |
Collapse
|
12
|
Jasu A, Ray RR. Biofilm mediated strategies to mitigate heavy metal pollution: A critical review in metal bioremediation. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2021. [DOI: 10.1016/j.bcab.2021.102183] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
|
13
|
Scortichini M, Loreti S, Pucci N, Scala V, Tatulli G, Verweire D, Oehl M, Widmer U, Codina JM, Hertl P, Cesari G, De Caroli M, Angilè F, Migoni D, Del Coco L, Girelli CR, Dalessandro G, Fanizzi FP. Progress towards Sustainable Control of Xylella fastidiosa subsp. pauca in Olive Groves of Salento (Apulia, Italy). Pathogens 2021; 10:668. [PMID: 34072394 PMCID: PMC8228964 DOI: 10.3390/pathogens10060668] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 05/19/2021] [Accepted: 05/26/2021] [Indexed: 11/16/2022] Open
Abstract
Xylella fastidiosa subsp. pauca is the causal agent of "olive quick decline syndrome" in Salento (Apulia, Italy). On April 2015, we started interdisciplinary studies to provide a sustainable control strategy for this pathogen that threatens the multi-millennial olive agroecosystem of Salento. Confocal laser scanning microscopy and fluorescence quantification showed that a zinc-copper-citric acid biocomplex-Dentamet®-reached the olive xylem tissue either after the spraying of the canopy or injection into the trunk, demonstrating its effective systemicity. The biocomplex showed in vitro bactericidal activity towards all X. fastidiosa subspecies. A mid-term evaluation of the control strategy performed in some olive groves of Salento indicated that this biocomplex significantly reduced both the symptoms and X. f. subsp. pauca cell concentration within the leaves of the local cultivars Ogliarola salentina and Cellina di Nardò. The treated trees started again to yield. A 1H-NMR metabolomic approach revealed, upon the treatments, a consistent increase in malic acid and γ-aminobutyrate for Ogliarola salentina and Cellina di Nardò trees, respectively. A novel endotherapy technique allowed injection of Dentamet® at low pressure directly into the vascular system of the tree and is currently under study for the promotion of resprouting in severely attacked trees. There are currently more than 700 ha of olive groves in Salento where this strategy is being applied to control X. f. subsp. pauca. These results collectively demonstrate an efficient, simple, low-cost, and environmentally sustainable strategy to control this pathogen in Salento.
Collapse
Affiliation(s)
- Marco Scortichini
- Research Centre for Olive, Fruit Trees and Citrus Crops, Council for Agricultural Research and Economics (CREA), 00134 Roma, Italy
| | - Stefania Loreti
- Research Centre for Plant Protection and Certification, Council for Agricultural Research and Economics (CREA), 00156 Roma, Italy; (S.L.); (N.P.); (V.S.); (G.T.)
| | - Nicoletta Pucci
- Research Centre for Plant Protection and Certification, Council for Agricultural Research and Economics (CREA), 00156 Roma, Italy; (S.L.); (N.P.); (V.S.); (G.T.)
| | - Valeria Scala
- Research Centre for Plant Protection and Certification, Council for Agricultural Research and Economics (CREA), 00156 Roma, Italy; (S.L.); (N.P.); (V.S.); (G.T.)
| | - Giuseppe Tatulli
- Research Centre for Plant Protection and Certification, Council for Agricultural Research and Economics (CREA), 00156 Roma, Italy; (S.L.); (N.P.); (V.S.); (G.T.)
| | - Dimitri Verweire
- Invaio Sciences, Cambridge, MA 02138, USA; (D.V.); (M.O.); (U.W.); (J.M.C.); (P.H.)
| | - Michael Oehl
- Invaio Sciences, Cambridge, MA 02138, USA; (D.V.); (M.O.); (U.W.); (J.M.C.); (P.H.)
| | - Urs Widmer
- Invaio Sciences, Cambridge, MA 02138, USA; (D.V.); (M.O.); (U.W.); (J.M.C.); (P.H.)
| | - Josep Massana Codina
- Invaio Sciences, Cambridge, MA 02138, USA; (D.V.); (M.O.); (U.W.); (J.M.C.); (P.H.)
| | - Peter Hertl
- Invaio Sciences, Cambridge, MA 02138, USA; (D.V.); (M.O.); (U.W.); (J.M.C.); (P.H.)
| | | | - Monica De Caroli
- Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Monteroni-Lecce, Italy; (M.D.C.); (F.A.); (D.M.); (L.D.C.); (C.R.G.); (G.D.); (F.P.F.)
| | - Federica Angilè
- Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Monteroni-Lecce, Italy; (M.D.C.); (F.A.); (D.M.); (L.D.C.); (C.R.G.); (G.D.); (F.P.F.)
| | - Danilo Migoni
- Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Monteroni-Lecce, Italy; (M.D.C.); (F.A.); (D.M.); (L.D.C.); (C.R.G.); (G.D.); (F.P.F.)
| | - Laura Del Coco
- Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Monteroni-Lecce, Italy; (M.D.C.); (F.A.); (D.M.); (L.D.C.); (C.R.G.); (G.D.); (F.P.F.)
| | - Chiara Roberta Girelli
- Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Monteroni-Lecce, Italy; (M.D.C.); (F.A.); (D.M.); (L.D.C.); (C.R.G.); (G.D.); (F.P.F.)
| | - Giuseppe Dalessandro
- Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Monteroni-Lecce, Italy; (M.D.C.); (F.A.); (D.M.); (L.D.C.); (C.R.G.); (G.D.); (F.P.F.)
| | - Francesco Paolo Fanizzi
- Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Monteroni-Lecce, Italy; (M.D.C.); (F.A.); (D.M.); (L.D.C.); (C.R.G.); (G.D.); (F.P.F.)
| |
Collapse
|
14
|
Riefolo C, Antelmi I, Castrignanò A, Ruggieri S, Galeone C, Belmonte A, Muolo MR, Ranieri NA, Labarile R, Gadaleta G, Nigro F. Assessment of the Hyperspectral Data Analysis as a Tool to Diagnose Xylella fastidiosa in the Asymptomatic Leaves of Olive Plants. PLANTS 2021; 10:plants10040683. [PMID: 33916301 PMCID: PMC8065538 DOI: 10.3390/plants10040683] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Revised: 03/30/2021] [Accepted: 03/30/2021] [Indexed: 11/16/2022]
Abstract
Xylella fastidiosa is a bacterial pathogen affecting many plant species worldwide. Recently, the subspecies pauca (Xfp) has been reported as the causal agent of a devastating disease on olive trees in the Salento area (Apulia region, southeastern Italy), where centenarian and millenarian plants constitute a great agronomic, economic, and landscape trait, as well as an important cultural heritage. It is, therefore, important to develop diagnostic tools able to detect the disease early, even when infected plants are still asymptomatic, to reduce the infection risk for the surrounding plants. The reference analysis is the quantitative real time-Polymerase-Chain-Reaction (qPCR) of the bacterial DNA. The aim of this work was to assess whether the analysis of hyperspectral data, using different statistical methods, was able to select with sufficient accuracy, which plants to analyze with PCR, to save time and economic resources. The study area was selected in the Municipality of Oria (Brindisi). Partial Least Square Regression (PLSR) and Canonical Discriminant Analysis (CDA) indicated that the most important bands were those related to the chlorophyll function, water, lignin content, as can also be seen from the wilting symptoms in Xfp-infected plants. The confusion matrix of CDA showed an overall accuracy of 0.67, but with a better capability to discriminate the infected plants. Finally, an unsupervised classification, using only spectral data, was able to discriminate the infected plants at a very early stage of infection. Then, in phase of testing qPCR should be performed only on the plants predicted as infected from hyperspectral data, thus, saving time and financial resources.
Collapse
Affiliation(s)
- Carmela Riefolo
- Research Centre for Agriculture and Environment, Council for Agricultural Research and Economics (CREA-AA), 70125 Bari, Italy;
- Correspondence: (C.R.); (F.N.)
| | - Ilaria Antelmi
- Dipartimento di Scienze del Suolo, della Pianta e degli Alimenti, Università degli Studi Aldo Moro, Via Amendola 165/A, 70126 Bari, Italy; (I.A.); (R.L.)
| | - Annamaria Castrignanò
- Department of Engineering and Geology (InGeo), Università degli Studi Gabriele D’Annunzio, Chieti-Pescara, 66013 Chieti, Italy;
| | - Sergio Ruggieri
- Research Centre for Agriculture and Environment, Council for Agricultural Research and Economics (CREA-AA), 70125 Bari, Italy;
| | - Ciro Galeone
- Water Research Institute, National Research Council (CNR-IRSA), 70125 Bari, Italy;
| | - Antonella Belmonte
- Institute for Electromagnetic Sensing of the Environment, National Research Council (CNR-IREA), 70126 Bari, Italy;
| | - Maria Rita Muolo
- Servizi di Informazione Territoriale S.r.l., 70015 Noci, Italy; (M.R.M.); (N.A.R.)
| | - Nicola A. Ranieri
- Servizi di Informazione Territoriale S.r.l., 70015 Noci, Italy; (M.R.M.); (N.A.R.)
| | - Rossella Labarile
- Dipartimento di Scienze del Suolo, della Pianta e degli Alimenti, Università degli Studi Aldo Moro, Via Amendola 165/A, 70126 Bari, Italy; (I.A.); (R.L.)
| | | | - Franco Nigro
- Dipartimento di Scienze del Suolo, della Pianta e degli Alimenti, Università degli Studi Aldo Moro, Via Amendola 165/A, 70126 Bari, Italy; (I.A.); (R.L.)
- Correspondence: (C.R.); (F.N.)
| |
Collapse
|
15
|
Tatulli G, Modesti V, Pucci N, Scala V, L’Aurora A, Lucchesi S, Salustri M, Scortichini M, Loreti S. Further In Vitro Assessment and Mid-Term Evaluation of Control Strategy of Xylella fastidiosa subsp. pauca in Olive Groves of Salento (Apulia, Italy). Pathogens 2021; 10:85. [PMID: 33478174 PMCID: PMC7835972 DOI: 10.3390/pathogens10010085] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 01/13/2021] [Accepted: 01/14/2021] [Indexed: 12/13/2022] Open
Abstract
During recent years; Xylella fastidiosa subsp. pauca (Xfp) has spread in Salento causing relevant damage to the olive groves. Measures to contain the spreading of the pathogen include the monitoring of the areas bordering the so-called "infected" zone and the tree eradication in case of positive detection. In order to provide a control strategy aimed to maintain the tree productivity in the infected areas, we further evaluated the in vitro and in planta mid-term effectiveness of a zinc-copper-citric acid biocomplex. The compound showed an in vitro bactericidal activity and inhibited the biofilm formation in representative strains of X. fastidiosa subspecies, including Xfp isolated in Apulia from olive trees. The field mid-term evaluation of the control strategy assessed by quantitative real-time PCR in 41 trees of two olive groves of the "infected" area revealed a low concentration of Xfp over the seasons upon the regular spraying of the biocomplex over 3 or 4 consecutive years. In particular, the bacterial concentration lowered in July and October with respect to March, after six consecutive treatments. The trend was not affected by the cultivar and it was similar either in the Xfp-sensitive cultivars Ogliarola salentina and Cellina di Nardò or in the Xfp-resistant Leccino. Moreover, the scoring of the number of wilted twigs over the seasons confirmed the trend. The efficacy of the treatment in the management of olive groves subjected to a high pathogen pressure is highlighted by the yielded a good oil production.
Collapse
Affiliation(s)
- Giuseppe Tatulli
- Council for Agricultural Research and Economics (CREA), Research Centre for Plant Protection and Certification, 00156 Roma, Italy; (G.T.); (V.M.); (N.P.); (V.S.); (A.L.); (S.L.)
| | - Vanessa Modesti
- Council for Agricultural Research and Economics (CREA), Research Centre for Plant Protection and Certification, 00156 Roma, Italy; (G.T.); (V.M.); (N.P.); (V.S.); (A.L.); (S.L.)
| | - Nicoletta Pucci
- Council for Agricultural Research and Economics (CREA), Research Centre for Plant Protection and Certification, 00156 Roma, Italy; (G.T.); (V.M.); (N.P.); (V.S.); (A.L.); (S.L.)
| | - Valeria Scala
- Council for Agricultural Research and Economics (CREA), Research Centre for Plant Protection and Certification, 00156 Roma, Italy; (G.T.); (V.M.); (N.P.); (V.S.); (A.L.); (S.L.)
| | - Alessia L’Aurora
- Council for Agricultural Research and Economics (CREA), Research Centre for Plant Protection and Certification, 00156 Roma, Italy; (G.T.); (V.M.); (N.P.); (V.S.); (A.L.); (S.L.)
| | - Simone Lucchesi
- Council for Agricultural Research and Economics (CREA), Research Centre for Plant Protection and Certification, 00156 Roma, Italy; (G.T.); (V.M.); (N.P.); (V.S.); (A.L.); (S.L.)
| | - Manuel Salustri
- Dipartimento di Biologia Ambientale, Sapienza University of Rome, 00185 Roma, Italy;
| | - Marco Scortichini
- Council for Agricultural Research and Economics (CREA), Research Centre for Olive, Fruit and Citrus Crops, 00134 Roma, Italy
| | - Stefania Loreti
- Council for Agricultural Research and Economics (CREA), Research Centre for Plant Protection and Certification, 00156 Roma, Italy; (G.T.); (V.M.); (N.P.); (V.S.); (A.L.); (S.L.)
| |
Collapse
|
16
|
Gao K, Hu Y, Guo C, Ke C, Lu G, Dang Z. Mobilization of arsenic during reductive dissolution of As(V)-bearing jarosite by a sulfate reducing bacterium. JOURNAL OF HAZARDOUS MATERIALS 2021; 402:123717. [PMID: 33254757 DOI: 10.1016/j.jhazmat.2020.123717] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2020] [Revised: 07/24/2020] [Accepted: 08/11/2020] [Indexed: 06/12/2023]
Abstract
Microbial sulfidization of arsenic (As)-bearing jarosite involves complex processes and is yet to be fully elucidated. Here, we investigated the behavior of As during reductive dissolution of As(V)-bearing jarosite by a pure sulfate reducing bacterium with or without dissolved SO42- amendment. Changes of aqueous chemistry, mineralogical characteristics, and As speciation were examined in batch experiments. The results indicated that jarosite was mostly replaced by mackinawite in the system with added SO42-. In the medium without additional SO42-, mackinawite, vivianite, pyrite, and magnetite formed as secondary Fe minerals, though 24.55 % of total Fe was in form of an aqueous Fe2+ phase. The produced Fe2+ in turn catalyzed the transformation of jarosite. At the end of the incubation, 41.99 % and 48.10 % of As in the solid phase got released into the aqueous phase in the systems with and without added SO42-, respectively. The addition of dissolved SO42- mitigated the mobilization of As into the aqueous phase. In addition, all As5+ on the solid surface was reduced to As3+ during the microbial sulfidization of As-bearing jarosite. These findings are important for a better understanding of geochemical cycling of elements As, S, and Fe in acid mine drainage and acid sulfate soil environments.
Collapse
Affiliation(s)
- Kun Gao
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, PR China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, South China University of Technology, Guangzhou 510006, PR China
| | - Yue Hu
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, PR China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, South China University of Technology, Guangzhou 510006, PR China
| | - Chuling Guo
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, PR China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, South China University of Technology, Guangzhou 510006, PR China.
| | - Changdong Ke
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, PR China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, South China University of Technology, Guangzhou 510006, PR China
| | - Guining Lu
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, PR China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, South China University of Technology, Guangzhou 510006, PR China
| | - Zhi Dang
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, PR China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, South China University of Technology, Guangzhou 510006, PR China.
| |
Collapse
|
17
|
Asteggiano A, Franceschi P, Zorzi M, Aigotti R, Dal Bello F, Baldassarre F, Lops F, Carlucci A, Medana C, Ciccarella G. HPLC-HRMS Global Metabolomics Approach for the Diagnosis of "Olive Quick Decline Syndrome" Markers in Olive Trees Leaves. Metabolites 2021; 11:metabo11010040. [PMID: 33429872 PMCID: PMC7827768 DOI: 10.3390/metabo11010040] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 12/28/2020] [Accepted: 01/05/2021] [Indexed: 12/25/2022] Open
Abstract
Olive quick decline syndrome (OQDS) is a multifactorial disease affecting olive plants. The onset of this economically devastating disease has been associated with a Gram-negative plant pathogen called Xylella fastidiosa (Xf). Liquid chromatography separation coupled to high-resolution mass spectrometry detection is one the most widely applied technologies in metabolomics, as it provides a blend of rapid, sensitive, and selective qualitative and quantitative analyses with the ability to identify metabolites. The purpose of this work is the development of a global metabolomics mass spectrometry assay able to identify OQDS molecular markers that could discriminate between healthy (HP) and infected (OP) olive tree leaves. Results obtained via multivariate analysis through an HPLC-ESI HRMS platform (LTQ-Orbitrap from Thermo Scientific) show a clear separation between HP and OP samples. Among the differentially expressed metabolites, 18 different organic compounds highly expressed in the OP group were annotated; results obtained by this metabolomic approach could be used as a fast and reliable method for the biochemical characterization of OQDS and to develop targeted MS approaches for OQDS detection by foliage analysis.
Collapse
Affiliation(s)
- Alberto Asteggiano
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Via Pietro Giuria 5, 10125 Torino, Italy; (A.A.); (M.Z.); (R.A.); (F.D.B.)
| | - Pietro Franceschi
- Unit of Computational Biology, IASMA Research and Innovation Centre, Fondazione Edmund Mach via E. Mach, 1, 38010 San Michele all’ Adige, Italy;
| | - Michael Zorzi
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Via Pietro Giuria 5, 10125 Torino, Italy; (A.A.); (M.Z.); (R.A.); (F.D.B.)
| | - Riccardo Aigotti
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Via Pietro Giuria 5, 10125 Torino, Italy; (A.A.); (M.Z.); (R.A.); (F.D.B.)
| | - Federica Dal Bello
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Via Pietro Giuria 5, 10125 Torino, Italy; (A.A.); (M.Z.); (R.A.); (F.D.B.)
| | - Francesca Baldassarre
- Biological and Environmental Sciences Department, UdR INSTM of Lecce University of Salento, Via Monteroni, 73100 Lecce, Italy;
- Institute of Nanotechnology, CNR NANOTEC, Consiglio Nazionale delle Ricerche, Via Monteroni, 73100 Lecce, Italy
| | - Francesco Lops
- Department of Science of Agriculture, Food and Environment, University of Foggia, Via Napoli, 25, 71122 Foggia, Italy; (F.L.); (A.C.)
| | - Antonia Carlucci
- Department of Science of Agriculture, Food and Environment, University of Foggia, Via Napoli, 25, 71122 Foggia, Italy; (F.L.); (A.C.)
| | - Claudio Medana
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Via Pietro Giuria 5, 10125 Torino, Italy; (A.A.); (M.Z.); (R.A.); (F.D.B.)
- Correspondence: (C.M.); (G.C.); Tel.: +39-011-670-5240 (C.M.); +39-083-231-9810 (G.C.)
| | - Giuseppe Ciccarella
- Biological and Environmental Sciences Department, UdR INSTM of Lecce University of Salento, Via Monteroni, 73100 Lecce, Italy;
- Institute of Nanotechnology, CNR NANOTEC, Consiglio Nazionale delle Ricerche, Via Monteroni, 73100 Lecce, Italy
- Correspondence: (C.M.); (G.C.); Tel.: +39-011-670-5240 (C.M.); +39-083-231-9810 (G.C.)
| |
Collapse
|
18
|
Naranjo E, Merfa MV, Santra S, Ozcan A, Johnson E, Cobine PA, De La Fuente L. Zinkicide Is a ZnO-Based Nanoformulation with Bactericidal Activity against Liberibacter crescens in Batch Cultures and in Microfluidic Chambers Simulating Plant Vascular Systems. Appl Environ Microbiol 2020; 86:e00788-20. [PMID: 32561578 PMCID: PMC7414956 DOI: 10.1128/aem.00788-20] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Accepted: 06/12/2020] [Indexed: 01/09/2023] Open
Abstract
Phloem-limited bacterial "Candidatus Liberibacter" species are associated with incurable plant diseases worldwide. Antimicrobial treatments for these pathogens are challenging due to the difficulty of reaching the vascular tissue they occupy at bactericidal concentrations. Here, in vitro antimicrobial mechanisms of Zinkicide TMN110 (ZnK), a nonphytotoxic zinc oxide (ZnO)-based nanoformulation, were compared to those of bulk ZnO (b-ZnO) using as a model the only culturable species of the genus, Liberibacter crescens Minimum bactericidal concentration (MBC) determination and time-kill assays showed that ZnK has a bactericidal effect against L. crescens, whereas b-ZnO is bacteriostatic. When ZnK was used at the MBC (150 ppm), its antimicrobial mechanisms included an increase in Zn solubility, generation of intracellular reactive oxygen species, lipid peroxidation, and cell membrane disruption; all of these were of greater intensity than those of b-ZnO. Inhibition of biofilms, which are important during insect vector colonization, was stronger by ZnK than by b-ZnO at concentrations between 2.5 and 10 ppm in batch cultures; however, neither ZnK nor b-ZnO removed L. crescens preformed biofilms when applied between 100 and 400 ppm. In microfluidic chambers simulating source-to-sink phloem movement, ZnK significantly outperformed b-ZnO in Zn mobilization and bactericidal activity against L. crescens planktonic cells in sink reservoirs. In microfluidic chamber assays assessing antibiofilm activity, ZnK displayed a significantly enhanced bactericidal activity against L. crescens individual attached cells as well as preformed biofilms compared to that of b-ZnO. The superior mobility and antimicrobial activity of ZnK in microenvironments make this formulation a promising product to control plant diseases caused by "Candidatus Liberibacter" species and other plant vascular pathogens.IMPORTANCE "Candidatus Liberibacter" species are associated with incurable plant diseases that have caused billions of dollars of losses for United States and world agriculture. Chemical control of these pathogens is complicated, because their life cycle combines intracellular vascular stages in plant hosts with transmission by highly mobile insect vectors. To date, "Candidatus Liberibacter" species are mostly unculturable, except for Liberibacter crescens, a member of the genus that has been used as a model for in vitro assays. Here, we evaluated the potential of Zinkicide (ZnK) as an antimicrobial against "Candidatus Liberibacter" species in batch cultures and under flow conditions, using L. crescens as a biological model. ZnK displayed bactericidal activity against L. crescens in batch cultures and showed increased mobility and bactericidal activity in microfluidic devices resembling "Candidatus Liberibacter" species natural habitats. ZnK performance observed here against L. crescens makes this compound a promising candidate to control plant diseases caused by vascular pathogens.
Collapse
Affiliation(s)
- Eber Naranjo
- Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama, USA
| | - Marcus V Merfa
- Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama, USA
| | - Swadeshmukul Santra
- NanoScience Technology Center, University of Central Florida, Orlando, Florida, USA
- Department of Chemistry, University of Central Florida, Orlando, Florida, USA
- Department of Materials Science and Engineering, University of Central Florida, Orlando, Florida, USA
- Burnett School of Biomedical Sciences, University of Central Florida, Orlando, Florida, USA
| | - Ali Ozcan
- NanoScience Technology Center, University of Central Florida, Orlando, Florida, USA
- Department of Chemistry, University of Central Florida, Orlando, Florida, USA
- Vocational School of Technical Sciences, Karamanoglu Mehmetbey University, Karaman, Turkey
| | - Evan Johnson
- Citrus Research and Education Center, University of Florida, Lake Alfred, Florida, USA
| | - Paul A Cobine
- Department of Biological Sciences, Auburn University, Auburn, Alabama, USA
| | - Leonardo De La Fuente
- Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama, USA
| |
Collapse
|
19
|
Baró A, Badosa E, Montesinos L, Feliu L, Planas M, Montesinos E, Bonaterra A. Screening and identification of BP100 peptide conjugates active against Xylella fastidiosa using a viability-qPCR method. BMC Microbiol 2020; 20:229. [PMID: 32727358 PMCID: PMC7392676 DOI: 10.1186/s12866-020-01915-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Accepted: 07/20/2020] [Indexed: 12/16/2022] Open
Abstract
Background Xylella fastidiosa is one of the most harmful bacterial plant pathogens worldwide, causing a variety of diseases, with huge economic impact to agriculture and environment. Although it has been extensively studied, there are no therapeutic solutions to suppress disease development in infected plants. In this context, antimicrobial peptides represent promising alternatives to traditional compounds due to their activity against a wide range of plant pathogens, their low cytotoxicity, their mode of action that make resistance more difficult and their availability for being expressed in plants. Results Peptide conjugates derived from the lead peptide BP100 and fragments of cecropin, magainin or melittin were selected and tested against the plant pathogenic bacteria X. fastidiosa. In order to screen the activity of these antimicrobials, and due to the fastidious nature of the pathogen, a methodology consisting of a contact test coupled with the viability-quantitative PCR (v-qPCR) method was developed. The nucleic acid-binding dye PEMAX was used to selectively quantify viable cells by v-qPCR. In addition, the primer set XF16S-3 amplifying a 279 bp fragment was selected as the most suitable for v-qPCR. The performance of the method was assessed by comparing v-qPCR viable cells estimation with conventional qPCR and plate counting. When cells were treated with peptide conjugates derived from BP100, the observed differences between methods suggested that, in addition to cell death due to the lytic effect of the peptides, there was an induction of the viable but non-culturable state in cells. Notably, a contact test coupled to v-qPCR allowed fast and accurate screening of antimicrobial peptides, and led to the identification of new peptide conjugates active against X. fastidiosa. Conclusions Antimicrobial peptides active against X. fastidiosa have been identified using an optimized methodology that quantifies viable cells without a cultivation stage, avoiding underestimation or false negative detection of the pathogen due to the viable but non-culturable state, and overestimation of the viable population observed using qPCR. These findings provide new alternative compounds for being tested in planta for the control of X. fastidiosa, and a methodology that enables the fast screening of a large amount of antimicrobials against this plant pathogenic bacterium.
Collapse
Affiliation(s)
- Aina Baró
- Laboratory of Plant Pathology, Institute of Food and Agricultural Technology-CIDSAV-XaRTA, University of Girona, Girona, Spain
| | - Esther Badosa
- Laboratory of Plant Pathology, Institute of Food and Agricultural Technology-CIDSAV-XaRTA, University of Girona, Girona, Spain
| | - Laura Montesinos
- Laboratory of Plant Pathology, Institute of Food and Agricultural Technology-CIDSAV-XaRTA, University of Girona, Girona, Spain
| | - Lidia Feliu
- LIPPSO, Department of Chemistry, University of Girona, Girona, Spain
| | - Marta Planas
- LIPPSO, Department of Chemistry, University of Girona, Girona, Spain
| | - Emilio Montesinos
- Laboratory of Plant Pathology, Institute of Food and Agricultural Technology-CIDSAV-XaRTA, University of Girona, Girona, Spain
| | - Anna Bonaterra
- Laboratory of Plant Pathology, Institute of Food and Agricultural Technology-CIDSAV-XaRTA, University of Girona, Girona, Spain.
| |
Collapse
|
20
|
Baró A, Mora I, Montesinos L, Montesinos E. Differential Susceptibility of Xylella fastidiosa Strains to Synthetic Bactericidal Peptides. PHYTOPATHOLOGY 2020; 110:1018-1026. [PMID: 31985337 DOI: 10.1094/phyto-12-19-0477-r] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The kinetics of cell inactivation and the susceptibility of Xylella fastidiosa subspecies fastidiosa, multiplex, and pauca to synthetic antimicrobial peptides from two libraries (CECMEL11 and CYCLO10) were studied. The bactericidal effect was dependent on the relative concentrations of peptide and bacterial cells, and was influenced by the diluent, either buffer or sap. The most bactericidal and lytic peptide was BP178, an enlarged derivative of the amphipathic cationic linear undecapeptide BP100. The maximum reduction in survivors after BP178 treatment occurred within the first 10 to 20 min of contact and at micromolar concentrations (<10 μM), resulting in pore formation in cell membranes, abundant production of outer membrane vesicles, and lysis. A threshold ratio of 109 molecules of peptide per bacterial cell was estimated to be necessary to initiate cell inactivation. There was a differential susceptibility to BP178 among strains, with DD1 being the most resistant and CFBP 8173 the most susceptible. Moreover, strains showed a proportion of cells under the viable but nonculturable state, which was highly variable among strains. These findings may have implications for managing the diseases caused by X. fastidiosa.
Collapse
Affiliation(s)
- Aina Baró
- Institute of Food and Agricultural Technology-XaRTA-CIDSAV, University of Girona, C/ Maria Aurèlia Capmany 61, 17003 Girona, Spain
| | - Isabel Mora
- Institute of Food and Agricultural Technology-XaRTA-CIDSAV, University of Girona, C/ Maria Aurèlia Capmany 61, 17003 Girona, Spain
| | - Laura Montesinos
- Institute of Food and Agricultural Technology-XaRTA-CIDSAV, University of Girona, C/ Maria Aurèlia Capmany 61, 17003 Girona, Spain
| | - Emilio Montesinos
- Institute of Food and Agricultural Technology-XaRTA-CIDSAV, University of Girona, C/ Maria Aurèlia Capmany 61, 17003 Girona, Spain
| |
Collapse
|
21
|
Abstract
Xylella fastidiosa is one of the most important threats to plant health worldwide, causing disease in the Americas on a range of agricultural crops and trees, and recently associated with a critical epidemic affecting olive trees in Europe. A main challenge for the detection of the pathogen and the development of physiological studies is its fastidious growth, as the generation time can vary from 10 to 100 h for some strains. This physiological peculiarity is shared with several human pathogens and is poorly understood. We performed an analysis of the metabolic capabilities of X. fastidiosa through a genome-scale metabolic model of the bacterium. This model was reconstructed and manually curated using experiments and bibliographical evidence. Our study revealed that fastidious growth most probably results from different metabolic specificities such as the absence of highly efficient enzymes or a global inefficiency in virulence factor production. These results support the idea that the fragility of the metabolic network may have been shaped during evolution to lead to the self-limiting behavior of X. fastidiosa. High proliferation rate and robustness are vital characteristics of bacterial pathogens that successfully colonize their hosts. The observation of drastically slow growth in some pathogens is thus paradoxical and remains unexplained. In this study, we sought to understand the slow (fastidious) growth of the plant pathogen Xylella fastidiosa. Using genome-scale metabolic network reconstruction, modeling, and experimental validation, we explored its metabolic capabilities. Despite genome reduction and slow growth, the pathogen’s metabolic network is complete but strikingly minimalist and lacking in robustness. Most alternative reactions were missing, especially those favoring fast growth, and were replaced by less efficient paths. We also found that the production of some virulence factors imposes a heavy burden on growth. Interestingly, some specific determinants of fastidious growth were also found in other slow-growing pathogens, enriching the view that these metabolic peculiarities are a pathogenicity strategy to remain at a low population level. IMPORTANCEXylella fastidiosa is one of the most important threats to plant health worldwide, causing disease in the Americas on a range of agricultural crops and trees, and recently associated with a critical epidemic affecting olive trees in Europe. A main challenge for the detection of the pathogen and the development of physiological studies is its fastidious growth, as the generation time can vary from 10 to 100 h for some strains. This physiological peculiarity is shared with several human pathogens and is poorly understood. We performed an analysis of the metabolic capabilities of X. fastidiosa through a genome-scale metabolic model of the bacterium. This model was reconstructed and manually curated using experiments and bibliographical evidence. Our study revealed that fastidious growth most probably results from different metabolic specificities such as the absence of highly efficient enzymes or a global inefficiency in virulence factor production. These results support the idea that the fragility of the metabolic network may have been shaped during evolution to lead to the self-limiting behavior of X. fastidiosa.
Collapse
|
22
|
Cattò C, De Vincenti L, Cappitelli F, D’Attoma G, Saponari M, Villa F, Forlani F. Non-Lethal Effects of N-Acetylcysteine on Xylella fastidiosa Strain De Donno Biofilm Formation and Detachment. Microorganisms 2019; 7:E656. [PMID: 31817370 PMCID: PMC6955915 DOI: 10.3390/microorganisms7120656] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Revised: 11/28/2019] [Accepted: 12/03/2019] [Indexed: 01/03/2023] Open
Abstract
This study investigated in-vitro the non-lethal effects of N-acetylcysteine (NAC) on Xylella fastidiosa subspecies pauca strain De Donno (Xf-DD) biofilm. This strain was isolated from the olive trees affected by the olive quick decline syndrome in southern Italy. Xf-DD was first exposed to non-lethal concentrations of NAC from 0.05 to 1000 µM. Cell surface adhesion was dramatically reduced at 500 µM NAC (-47%), hence, this concentration was selected for investigating the effects of pre-, post- and co-treatments on biofilm physiology and structural development, oxidative homeostasis, and biofilm detachment. Even though 500 µM NAC reduced bacterial attachment to surfaces, compared to the control samples, it promoted Xf-DD biofilm formation by increasing: (i) biofilm biomass by up to 78% in the co-treatment, (ii) matrix polysaccharides production by up to 72% in the pre-treatment, and (iii) reactive oxygen species levels by 3.5-fold in the co-treatment. Xf-DD biofilm detachment without and with NAC was also investigated. The NAC treatment did not increase biofilm detachment, compared to the control samples. All these findings suggested that, at 500 µM, NAC diversified the phenotypes in Xf-DD biofilm, promoting biofilm formation (hyper-biofilm-forming phenotype) and discouraging biofilm detachment (hyper-attachment phenotype), while increasing oxidative stress level in the biofilm.
Collapse
Affiliation(s)
- Cristina Cattò
- Department of Food, Environmental and Nutritional Sciences, Università degli Studi di Milano, via Celoria 2, 20133 Milano, Italy; (C.C.); (L.D.V.); (F.C.); (F.F.)
| | - Luca De Vincenti
- Department of Food, Environmental and Nutritional Sciences, Università degli Studi di Milano, via Celoria 2, 20133 Milano, Italy; (C.C.); (L.D.V.); (F.C.); (F.F.)
| | - Francesca Cappitelli
- Department of Food, Environmental and Nutritional Sciences, Università degli Studi di Milano, via Celoria 2, 20133 Milano, Italy; (C.C.); (L.D.V.); (F.C.); (F.F.)
| | - Giusy D’Attoma
- Institute for Sustainable Plant Protection, Consiglio Nazionale delle Ricerche, via Amendola 165/A, 70126 Bari, Italy (M.S.)
| | - Maria Saponari
- Institute for Sustainable Plant Protection, Consiglio Nazionale delle Ricerche, via Amendola 165/A, 70126 Bari, Italy (M.S.)
| | - Federica Villa
- Department of Food, Environmental and Nutritional Sciences, Università degli Studi di Milano, via Celoria 2, 20133 Milano, Italy; (C.C.); (L.D.V.); (F.C.); (F.F.)
| | - Fabio Forlani
- Department of Food, Environmental and Nutritional Sciences, Università degli Studi di Milano, via Celoria 2, 20133 Milano, Italy; (C.C.); (L.D.V.); (F.C.); (F.F.)
| |
Collapse
|
23
|
Chen H, De La Fuente L. Calcium transcriptionally regulates movement, recombination and other functions of Xylella fastidiosa under constant flow inside microfluidic chambers. Microb Biotechnol 2019; 13:548-561. [PMID: 31729188 PMCID: PMC7017821 DOI: 10.1111/1751-7915.13512] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Revised: 10/25/2019] [Accepted: 10/28/2019] [Indexed: 01/08/2023] Open
Abstract
Xylella fastidiosa is a xylem‐limited bacterial pathogen causing devastating diseases in many economically important crops. Calcium (Ca) is a major inorganic nutrient in xylem sap that influences virulence‐related traits of this pathogen, including biofilm formation and twitching motility. This study aimed to adapt a microfluidic system, which mimics the natural habitat of X. fastidiosa, for whole transcriptome analysis under flow conditions. A microfluidic chamber with two parallel channels was used, and RNA isolated from cells grown inside the system was analysed by RNA‐Seq. Ca transcriptionally regulated the machinery of type IV pili and other genes related to pathogenicity and host adaptation. Results were compared to our previous RNA‐Seq study in biofilm cells in batch cultures (Parker et al., 2016, Environ Microbiol 18, 1620). Ca‐regulated genes in both studies belonged to similar functional categories, but the number and tendencies (up‐/downregulation) of regulated genes were different. Recombination‐related genes were upregulated by Ca, and we proved experimentally that 2 mM Ca enhances natural transformation frequency. Taken together, our results suggest that the regulatory role of Ca in X. fastidiosa acts differently during growth in flow or batch conditions, and this can correlate to the different phases of growth (planktonic and biofilm) during the infection process.
Collapse
Affiliation(s)
- Hongyu Chen
- Department of Entomology and Plant Pathology, Auburn University, Auburn, AL, 36849, USA
| | - Leonardo De La Fuente
- Department of Entomology and Plant Pathology, Auburn University, Auburn, AL, 36849, USA
| |
Collapse
|
24
|
Cheng G, Ning J, Ahmed S, Huang J, Ullah R, An B, Hao H, Dai M, Huang L, Wang X, Yuan Z. Selection and dissemination of antimicrobial resistance in Agri-food production. Antimicrob Resist Infect Control 2019; 8:158. [PMID: 31649815 PMCID: PMC6805589 DOI: 10.1186/s13756-019-0623-2] [Citation(s) in RCA: 70] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Accepted: 10/09/2019] [Indexed: 12/14/2022] Open
Abstract
Public unrest about the use of antimicrobial agents in farming practice is the leading cause of increasing and the emergences of Multi-drug Resistant Bacteria that have placed pressure on the agri-food industry to act. The usage of antimicrobials in food and agriculture have direct or indirect effects on the development of Antimicrobial resistance (AMR) by bacteria associated with animals and plants which may enter the food chain through consumption of meat, fish, vegetables or some other food sources. In addition to antimicrobials, recent reports have shown that AMR is associated with tolerance to heavy metals existing naturally or used in agri-food production. Besides, biocides including disinfectants, antiseptics and preservatives which are widely used in farms and slaughter houses may also contribute in the development of AMR. Though the direct transmission of AMR from food-animals and related environment to human is still vague and debatable, the risk should not be neglected. Therefore, combined global efforts are necessary for the proper use of antimicrobials, heavy metals and biocides in agri-food production to control the development of AMR. These collective measures will preserve the effectiveness of existing antimicrobials for future generations.
Collapse
Affiliation(s)
- Guyue Cheng
- 1MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University, Wuhan, 430070 China
| | - Jianan Ning
- 1MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University, Wuhan, 430070 China
| | - Saeed Ahmed
- 1MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University, Wuhan, 430070 China
| | - Junhong Huang
- 1MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University, Wuhan, 430070 China
| | - Rizwan Ullah
- 3State key laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070 China
| | - Boyu An
- 1MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University, Wuhan, 430070 China
| | - Haihong Hao
- 1MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University, Wuhan, 430070 China
| | - Menghong Dai
- 1MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University, Wuhan, 430070 China
| | - Lingli Huang
- 2National Reference Laboratory of Veterinary Drug Residues (HZAU) and MOA Key Laboratory for the Detection of Veterinary Drug Residues in Foods, Huazhong Agricultural University, Wuhan, 430070 China
| | - Xu Wang
- 1MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University, Wuhan, 430070 China
| | - Zonghui Yuan
- 1MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University, Wuhan, 430070 China.,2National Reference Laboratory of Veterinary Drug Residues (HZAU) and MOA Key Laboratory for the Detection of Veterinary Drug Residues in Foods, Huazhong Agricultural University, Wuhan, 430070 China
| |
Collapse
|
25
|
Baldassarre F, De Stradis A, Altamura G, Vergaro V, Citti C, Cannazza G, Capodilupo AL, Dini L, Ciccarella G. Application of calcium carbonate nanocarriers for controlled release of phytodrugs against Xylella fastidiosa pathogen. PURE APPL CHEM 2019. [DOI: 10.1515/pac-2018-1223] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Abstract
Calcium carbonate-based hollow or porous particles are one of the preferred carriers for fabrication of drug delivery systems. We have developed an eco-friendly method to produce calcium carbonate nanocrystals, which have shown biocompatibility and optimal capacity to across cell membrane in human cell lines providing new tools in cancer therapy. The success of drug delivery systems has paved the way for the development of systems for controlled release of agrochemicals. In this work, we exploited calcium carbonate nanocrystals as carriers for targeted release of phytodrugs investigating a potential control strategy for the pathogen Xylella fastidiosa. This pathogen is the causal agent of the Olive Quick Decline Syndrome that is an unprecedented emergency in Italy and potentially in the rest of Europe. We studied nanocrystals interactions with bacteria cells and the application in planta to verify olive plants uptake. Ultrastructural analysis by electron microscopy shown an alteration of bacteria wall following nanocrystals interaction. Nanocrystals were adsorbed from roots and they translocated in plants tissues. Calcium carbonate carriers were able to encapsulate efficiently two types of antimicrobial substances and the potential efficacy was tested in experiment under greenhouse conditions.
Collapse
Affiliation(s)
- Francesca Baldassarre
- Biological and Environmental Sciences Department, UdR INSTM of Lecce University of Salento , Via Monteroni, 73100 Lecce , Italy
- Institute of Nanotechnology, CNR NANOTEC, Consiglio Nazionale delle Ricerche , Via Monteroni, 73100 Lecce , Italy
| | - Angelo De Stradis
- Institute for Sustainable Plant Protection, CNR – IPSP, Consiglio Nazionale delle Ricerche , Via Amendola 165/A, 70126 Bari , Italy
| | - Giuseppe Altamura
- Institute for Sustainable Plant Protection, CNR – IPSP, Consiglio Nazionale delle Ricerche , Via Amendola 165/A, 70126 Bari , Italy
| | - Viviana Vergaro
- Biological and Environmental Sciences Department, UdR INSTM of Lecce University of Salento , Via Monteroni, 73100 Lecce , Italy
- Institute of Nanotechnology, CNR NANOTEC, Consiglio Nazionale delle Ricerche , Via Monteroni, 73100 Lecce , Italy
| | - Cinzia Citti
- Institute of Nanotechnology, CNR NANOTEC, Consiglio Nazionale delle Ricerche , Via Monteroni, 73100 Lecce , Italy
- Department of Life Sciences , University of Modena and Reggio Emilia , Via G. Campi 103, 41125 Modena , Italy
| | - Giuseppe Cannazza
- Institute of Nanotechnology, CNR NANOTEC, Consiglio Nazionale delle Ricerche , Via Monteroni, 73100 Lecce , Italy
- Department of Life Sciences , University of Modena and Reggio Emilia , Via G. Campi 103, 41125 Modena , Italy
| | - Agostina L. Capodilupo
- Institute of Nanotechnology, CNR NANOTEC, Consiglio Nazionale delle Ricerche , Via Monteroni, 73100 Lecce , Italy
| | - Luciana Dini
- Department of Biology and Biotechnology “Charles Darwin” , University of Rome “La Sapienza” , Piazzale Aldo Moro 5, 00185 Roma , Italy
| | - Giuseppe Ciccarella
- Biological and Environmental Sciences Department, UdR INSTM of Lecce University of Salento , Via Monteroni, 73100 Lecce , Italy
- Institute of Nanotechnology, CNR NANOTEC, Consiglio Nazionale delle Ricerche , Via Monteroni, 73100 Lecce , Italy
| |
Collapse
|
26
|
Cabot C, Martos S, Llugany M, Gallego B, Tolrà R, Poschenrieder C. A Role for Zinc in Plant Defense Against Pathogens and Herbivores. FRONTIERS IN PLANT SCIENCE 2019; 10:1171. [PMID: 31649687 PMCID: PMC6794951 DOI: 10.3389/fpls.2019.01171] [Citation(s) in RCA: 113] [Impact Index Per Article: 22.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Accepted: 08/27/2019] [Indexed: 05/17/2023]
Abstract
Pests and diseases pose a threat to food security, which is nowadays aggravated by climate change and globalization. In this context, agricultural policies demand innovative approaches to more effectively manage resources and overcome the ecological issues raised by intensive farming. Optimization of plant mineral nutrition is a sustainable approach to ameliorate crop health and yield. Zinc is a micronutrient essential for all living organisms with a key role in growth, development, and defense. Competition for Zn affects the outcome of the host-attacker interaction in both plant and animal systems. In this review, we provide a clear framework of the different strategies involving low and high Zn concentrations launched by plants to fight their enemies. After briefly introducing the most relevant macro- and micronutrients for plant defense, the functions of Zn in plant protection are summarized with special emphasis on superoxide dismutases (SODs) and zinc finger proteins. Following, we cover recent meaningful studies identifying Zn-related passive and active mechanisms for plant protection. Finally, Zn-based strategies evolved by pathogens and pests to counteract plant defenses are discussed.
Collapse
Affiliation(s)
- Catalina Cabot
- Departament of Biology, Universitat de les Illes Balears, Palma, Spain
| | - Soledad Martos
- Plant Physiology Laboratory, Bioscience Faculty, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Mercè Llugany
- Plant Physiology Laboratory, Bioscience Faculty, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Berta Gallego
- Plant Physiology Laboratory, Bioscience Faculty, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Roser Tolrà
- Plant Physiology Laboratory, Bioscience Faculty, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Charlotte Poschenrieder
- Plant Physiology Laboratory, Bioscience Faculty, Universitat Autònoma de Barcelona, Barcelona, Spain
| |
Collapse
|
27
|
Sicard A, Merfa MV, Voeltz M, Zeilinger AR, De La Fuente L, Almeida RPP. Discriminating between viable and membrane-damaged cells of the plant pathogen Xylella fastidiosa. PLoS One 2019; 14:e0221119. [PMID: 31442247 PMCID: PMC6707623 DOI: 10.1371/journal.pone.0221119] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Accepted: 07/30/2019] [Indexed: 12/31/2022] Open
Abstract
Xylella fastidiosa is a plant pathogenic bacterium with devastating consequences to several crops of economic importance across the world. While this pathogen has been studied for over a century in the United States, several aspects of its biology remain to be investigated. Determining the physiological state of bacteria is essential to understand the effects of its interactions with different biotic and abiotic factors on cell viability. Although X. fastidiosa is culturable, its slow growing nature makes this technique cumbersome to assess the physiological state of cells present in a given environment. PMA-qPCR, i.e. the use of quantitative PCR combined with the pre-treatment of cells with the dye propidium monoazide, has been successfully used in a number of studies on human pathogens to calculate the proportion of viable cells, but has less frequently been tested on plant pathogens. We found that the use of a version of PMA, PMAxx, facilitated distinguishing between viable and non-viable cells based on cell membrane integrity in vitro and in planta. Additional experiments comparing the number of culturable, viable, and total cells in planta would help further confirm our initial results. Enhancers, intended to improve the efficacy of PMAxx, were not effective and appeared to be slightly toxic to X. fastidiosa.
Collapse
Affiliation(s)
- Anne Sicard
- Department of Environmental Science, Policy and Management, University of California, Berkeley, California, United States of America
| | - Marcus V. Merfa
- Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama, United States of America
| | - Michael Voeltz
- Department of Environmental Science, Policy and Management, University of California, Berkeley, California, United States of America
| | - Adam R. Zeilinger
- Department of Environmental Science, Policy and Management, University of California, Berkeley, California, United States of America
| | - Leonardo De La Fuente
- Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama, United States of America
| | - Rodrigo P. P. Almeida
- Department of Environmental Science, Policy and Management, University of California, Berkeley, California, United States of America
| |
Collapse
|
28
|
Roper C, Castro C, Ingel B. Xylella fastidiosa: bacterial parasitism with hallmarks of commensalism. CURRENT OPINION IN PLANT BIOLOGY 2019; 50:140-147. [PMID: 31229798 DOI: 10.1016/j.pbi.2019.05.005] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2019] [Revised: 05/17/2019] [Accepted: 05/20/2019] [Indexed: 06/09/2023]
Abstract
All organisms evolve in the presence of other organisms and these intimate associations are major drivers of evolution. Broadly speaking, these interactions are considered symbioses and can take on a full range of positive, negative or seemingly neutral interactions. Just two examples of these symbiotic interactions are parasitism and commensalism. Parasitism results in one partner benefitting while one partner suffers adverse consequences. Commensalism is a form of symbiosis where one partner benefits and the other partner is neutrally affected. Research efforts are more often focused on understanding parasitic symbioses related to disease, hence, much research is performed on identifying virulence factors to understand the fundamentals of pathogenesis. In turn, much less is understood about the fundamentals of commensal relationships. Here, we will take an introspective look at the plant-associated bacterium, Xylella fastidiosa. In some of its many plant hosts, this bacterium participates in seemingly commensal relationships while in other hosts, it causes devastating diseases that result in epidemics, making it a good model for exploring the determinants of where bacteria fall on the spectrum of parasitic and commensal relationships from both the microbial and the plant host perspective. Recent discoveries in how pathogenic X. fastidiosa imposes self-limiting behaviors upon itself indicate that even in its parasitic form, X. fastidiosa displays hallmarks of a commensal lifestyle. Understanding how commensalism can 'go wrong' and manifest into pathologies in specific hosts is a useful vantage point from which to study the determinants of virulence and pathogenicity.
Collapse
Affiliation(s)
- Caroline Roper
- Department of Microbiology and Plant Pathology, University of California, Riverside, 900 University Avenue, Riverside, CA 92521, United States.
| | - Claudia Castro
- Department of Microbiology and Plant Pathology, University of California, Riverside, 900 University Avenue, Riverside, CA 92521, United States
| | - Brian Ingel
- Department of Microbiology and Plant Pathology, University of California, Riverside, 900 University Avenue, Riverside, CA 92521, United States
| |
Collapse
|
29
|
Kan Y, Jiang N, Xu X, Lyu Q, Gopalakrishnan V, Walcott R, Burdman S, Li J, Luo L. Induction and Resuscitation of the Viable but Non-culturable (VBNC) State in Acidovorax citrulli, the Causal Agent of Bacterial Fruit Blotch of Cucurbitaceous Crops. Front Microbiol 2019; 10:1081. [PMID: 31156591 PMCID: PMC6529555 DOI: 10.3389/fmicb.2019.01081] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Accepted: 04/29/2019] [Indexed: 01/14/2023] Open
Abstract
Acidovorax citrulli is a gram-negative bacterium that infects a wide range of cucurbits causing bacterial fruit blotch (BFB) disease. Copper-based compounds are the most widely-used chemicals for managing BFB and other bacterial diseases in the field. Many bacteria can enter a viable but non-culturable (VBNC) state in response to stress, including exposure to copper, and recover the culturability when favorable conditions return. The present study demonstrates that A. citrulli strain AAC00-1 is able to enter into the VBNC state by treatment with different concentrations of copper sulfate. It took 3 h, 5 and 15 days for all viable cells to lose culturability upon exposure to copper sulfate concentrations of 50, 10, and 5 μM, respectively. The VBNC A. citrulli cells regained culturability when the Cu2+ ions were removed by chelation with EDTA or by transfer of cells to LB broth, a cell-free supernatant from a suspension of AAC00-1, oligotrophic media amended with casein hydrolysate or watermelon seedling juice. We also found that the VBNC cells induced by Cu2+ were unable to colonize or infect watermelon seedlings directly, but the resuscitated cells recovered full virulence equivalent to untreated bacterial cells in the log phase. To the best of our knowledge, this is the first report on the VBNC state in A. citrulli and the factors that facilitate resuscitation and restoration of pathogenicity.
Collapse
Affiliation(s)
- Yumin Kan
- Department of Plant Pathology, China Agricultural University, Beijing Key Laboratory of Seed Disease Testing and Control, Beijing, China
| | - Na Jiang
- Department of Plant Pathology, China Agricultural University, Beijing Key Laboratory of Seed Disease Testing and Control, Beijing, China
| | - Xin Xu
- Department of Plant Pathology, China Agricultural University, Beijing Key Laboratory of Seed Disease Testing and Control, Beijing, China
| | - Qingyang Lyu
- Department of Plant Pathology, China Agricultural University, Beijing Key Laboratory of Seed Disease Testing and Control, Beijing, China
| | - Vinoj Gopalakrishnan
- Department of Plant Pathology and Microbiology, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Ronald Walcott
- Department of Plant Pathology, University of Georgia, Athens, GA, United States
| | - Saul Burdman
- Department of Plant Pathology and Microbiology, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Jianqiang Li
- Department of Plant Pathology, China Agricultural University, Beijing Key Laboratory of Seed Disease Testing and Control, Beijing, China
| | - Laixin Luo
- Department of Plant Pathology, China Agricultural University, Beijing Key Laboratory of Seed Disease Testing and Control, Beijing, China
| |
Collapse
|
30
|
Girelli CR, Angilè F, Del Coco L, Migoni D, Zampella L, Marcelletti S, Cristella N, Marangi P, Scortichini M, Fanizzi FP. 1H-NMR Metabolite Fingerprinting Analysis Reveals a Disease Biomarker and a Field Treatment Response in Xylella fastidiosa subsp. pauca-Infected Olive Trees. PLANTS (BASEL, SWITZERLAND) 2019; 8:E115. [PMID: 31035723 PMCID: PMC6571561 DOI: 10.3390/plants8050115] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Revised: 04/24/2019] [Accepted: 04/26/2019] [Indexed: 12/16/2022]
Abstract
Xylella fastidiosa subsp. pauca is a xylem-limited bacterial phytopathogen currently found associated on many hectares with the "olive quick decline syndrome" in the Apulia region (Southern Italy), and the cultivars Ogliarola salentina and Cellina di Nardò result in being particularly sensitive to the disease. In order to find compounds showing the capability of reducing the population cell density of the pathogen within the leaves, we tested, in some olive orchards naturally-infected by the bacterium, a zinc-copper-citric acid biocomplex, namely Dentamet®, by spraying it to the crown, once per month, during spring and summer. The occurrence of the pathogen in the four olive orchards chosen for the trial was molecularly assessed. A 1H NMR metabolomic approach, in conjunction with a multivariate statistical analysis, was applied to investigate the metabolic pattern of both infected and treated adult olive cultivars, Ogliarola salentina and Cellina di Nardò trees, in two sampling periods, performed during the first year of the trial. For both cultivars and sampling periods, the orthogonal partial least squares discriminant analysis (OPLS-DA) gave good models of separation according to the treatment application. In both cultivars, some metabolites such as quinic acid, the aldehydic form of oleoeuropein, ligstroside and phenolic compounds, were consistently found as discriminative for the untreated olive trees in comparison with the Dentamet®-treated trees. Quinic acid, a precursor of lignin, was confirmed as a disease biomarker for the olive trees infected by X. fastidiosa subsp. pauca. When treated with Dentamet®, the two cultivars showed a distinct response. A consistent increase in malic acid was observed for the Ogliarola salentina trees, whereas in the Cellina di Nardò trees the treatments attenuate the metabolic response to the infection. To note that in Cellina di Nardò trees at the first sampling, an increase in γ-aminobutyric acid (GABA) was observed. This study highlights how the infection incited by X. fastidiosa subsp. pauca strongly modifies the overall metabolism of olive trees, and how a zinc-copper-citric acid biocomplex can induce an early re-programming of the metabolic pathways in the infected trees.
Collapse
Affiliation(s)
- Chiara Roberta Girelli
- Department of Biological and Environmental Sciences and Technologies, University of Salento, Prov.le Lecce-Monteroni, I-73100 Lecce, Italy.
| | - Federica Angilè
- Department of Biological and Environmental Sciences and Technologies, University of Salento, Prov.le Lecce-Monteroni, I-73100 Lecce, Italy.
| | - Laura Del Coco
- Department of Biological and Environmental Sciences and Technologies, University of Salento, Prov.le Lecce-Monteroni, I-73100 Lecce, Italy.
| | - Danilo Migoni
- Department of Biological and Environmental Sciences and Technologies, University of Salento, Prov.le Lecce-Monteroni, I-73100 Lecce, Italy.
| | - Luigi Zampella
- Council for Agricultural research and Economics-Research Centre for Olive, Fruit Trees and Citrus, Via Torrino, 3, I-81100, Caserta, Italy.
| | - Simone Marcelletti
- Council for Agricultural research and Economics-Research Centre for Olive, Fruit Trees and Citrus, Via Torrino, 3, I-81100, Caserta, Italy.
| | - Nicola Cristella
- Studio Agro-Ambientale ed Ingegneria Terranostra srls, Via XXIV Maggio, 10, I-74020 Lizzano (TA), Italy.
| | - Paolo Marangi
- Studio Agro-Ambientale ed Ingegneria Terranostra srls, Via XXIV Maggio, 10, I-74020 Lizzano (TA), Italy.
| | - Marco Scortichini
- Council for Agricultural research and Economics-Research Centre for Olive, Fruit Trees and Citrus, Via Torrino, 3, I-81100, Caserta, Italy.
| | - Francesco Paolo Fanizzi
- Department of Biological and Environmental Sciences and Technologies, University of Salento, Prov.le Lecce-Monteroni, I-73100 Lecce, Italy.
| |
Collapse
|
31
|
In Vitro Formation of Dickeya zeae MS1 Biofilm. Curr Microbiol 2018; 76:100-107. [PMID: 30390102 DOI: 10.1007/s00284-018-1593-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Accepted: 10/29/2018] [Indexed: 10/28/2022]
Abstract
Bacterial soft rot caused by Dickeya zeae MS1 (Erwinia chrysanthemi) is one of the most devastating banana diseases worldwide. However, knowledge of the development and ecological interactions of D. zeae MS1 biofilm is limited. Here, we visualized the development and architecture of D. zeae MS1 biofilm using confocal laser scanning microscopy, and we evaluated the ability of D. zeae MS1 to form biofilms under different environmental conditions (carbon sources, temperatures, pH levels and mineral elements) using a microtiter plate assay. We found that the development of D. zeae MS1 biofilm could be categorized into four phases and that mature biofilm consisted of a highly organized architecture of both bacterial cells and a self-produced matrix of extracellular polysaccharides. Furthermore, sucrose was the most suitable carbon source for supporting the growth of biofilm cells and that 32 °C and pH 7.0 were the most favorable of the temperatures and pH levels examined. Meanwhile, the addition of Ca2+, Fe2+, K+ and Na+ enhanced the formation of biofilm in minimal medium cultures, whereas 2.5 mM Cu2+ and Mn2+ was inhibitory. A better understanding of biofilm formation under different environmental parameters will improve our knowledge of the growth kinetics of D. zeae MS1 biofilm.
Collapse
|
32
|
Aggarwal M, Hussaini MY, De La Fuente L, Navarrete F, Cogan NG. A framework for model analysis across multiple experiment regimes: Investigating effects of zinc on Xylella fastidiosa as a case study. J Theor Biol 2018; 457:88-100. [PMID: 30138631 DOI: 10.1016/j.jtbi.2018.08.028] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Revised: 07/14/2018] [Accepted: 08/18/2018] [Indexed: 12/13/2022]
Abstract
Mathematical models are ubiquitous in analyzing dynamical biological systems. However, it might not be possible to explicitly account for the various sources of uncertainties in the model and the data if there is limited experimental data and information about the biological processes. The presence of uncertainty introduces problems with identifiability of the parameters of the model and determining appropriate regions to explore with respect to sensitivity and estimates of parameter values. Since the model analysis is likely dependent on the numerical estimates of the parameters, parameter identifiability should be addressed beforehand to capture biologically relevant parameter space. Here, we propose a framework which uses data from different experiment regimes to identify a region in the parameter space over which subsequent mathematical analysis can be conducted. Along with building confidence in the parameter estimates, it provides us with variations in the parameters due to changes in the experimental conditions. To determine significance of these variations, we conduct global sensitivity analysis, allowing us to make testable hypothesis for effects of changes in the experimental conditions on the biological system. As a case study, we develop a model for growth dynamics and biofilm formation of a bacterial plant pathogen, and use our framework to identify possible effects of zinc on the bacterial populations in different metabolic states. The framework reveals underlying issues with parameter identifiability and identifies a suitable region in the parameter space, sensitivity analysis over which informs us about the parameters that might be affected by addition of zinc. Moreover, these parameters prove to be identifiable in this region.
Collapse
Affiliation(s)
- Manu Aggarwal
- Department of Mathematics, Florida State University, Tallahassee, Florida, USA.
| | - M Y Hussaini
- Department of Mathematics, Florida State University, Tallahassee, Florida, USA
| | - Leonardo De La Fuente
- Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama, USA
| | - Fernando Navarrete
- Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama, USA
| | - N G Cogan
- Department of Mathematics, Florida State University, Tallahassee, Florida, USA
| |
Collapse
|
33
|
Bucci EM. Xylella fastidiosa , a new plant pathogen that threatens global farming: Ecology, molecular biology, search for remedies. Biochem Biophys Res Commun 2018; 502:173-182. [DOI: 10.1016/j.bbrc.2018.05.073] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Accepted: 05/12/2018] [Indexed: 11/30/2022]
|
34
|
Mosharaf MK, Tanvir MZH, Haque MM, Haque MA, Khan MAA, Molla AH, Alam MZ, Islam MS, Talukder MR. Metal-Adapted Bacteria Isolated From Wastewaters Produce Biofilms by Expressing Proteinaceous Curli Fimbriae and Cellulose Nanofibers. Front Microbiol 2018; 9:1334. [PMID: 29988579 PMCID: PMC6026672 DOI: 10.3389/fmicb.2018.01334] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2018] [Accepted: 05/31/2018] [Indexed: 11/13/2022] Open
Abstract
Bacterial biofilm plays a pivotal role in bioremediation of heavy metals from wastewaters. In this study, we isolated and identified different biofilm producing bacteria from wastewaters. We also characterized the biofilm matrix [i.e., extracellular polymeric substances (EPS)] produced by different bacteria. Out of 40 isolates from different wastewaters, only 11 (27.5%) isolates (static condition at 28°C) and 9 (22.5%) isolates (agitate and static conditions at 28 and 37°C) produced air–liquid (AL) and solid–air–liquid (SAL) biofilms, respectively, only on salt-optimized broth plus 2% glycerol (SOBG) but not in other media tested. Biomass biofilms and bacteria coupled with AL biofilms were significantly (P ≤ 0.001) varied in these isolates. Escherichia coli (isolate ENSD101 and ENST501), Enterobacter asburiae (ENSD102), Enterobacter ludwigii (ENSH201), Pseudomonas fluorescens (ENSH202 and ENSG304), uncultured Vitreoscilla sp. (ENSG301 and ENSG305), Acinetobacter lwoffii (ENSG302), Klebsiella pneumoniae (ENSG303), and Bacillus thuringiensis (ENSW401) were identified based on 16S rRNA gene sequencing. Scanning electron microscope (SEM) images revealed that biofilm matrix produced by E. asburiae ENSD102, uncultured Vitreoscilla sp. ENSG301, A. lwoffii ENSG302, and K. pneumoniae ENSG303 are highly fibrous, compact, and nicely interlinked as compared to the biofilm developed by E. ludwigii ENSH201 and B. thuringiensis ENSW401. X-ray diffraction (XRD) results indicated that biofilm matrix produced by E. asburiae ENSD102, uncultured Vitreoscilla sp. ENSG301, and A. lwoffii ENSG302 are non-crystalline amorphous nature. Fourier transform infrared (FTIR) spectroscopy showed that proteins and polysaccharides are the main components of the biofilms. Congo red binding results suggested that all these bacteria produced proteinaceous curli fimbriae and cellulose-rich polysaccharide. Production of cellulose was also confirmed by Calcofluor binding- and spectrophotometric assays. E. asburiae ENSD102, Vitreoscilla sp. ENSG301, and A. lwoffii ENSG302 were tested for their abilities to form the biofilms exposure to 0 to 2000 mg/L of copper sulfate (for Cu), zinc sulfate (for Zn), lead nitrate (for Pb), nickel chloride (for Ni), and potassium dichromate (for Cr), several concentrations of these metals activated the biofilm formation. The polysaccharides is known to sequester the heavy metals thus, these bacteria might be applied to remove the heavy metals from wastewater.
Collapse
Affiliation(s)
- M K Mosharaf
- Department of Environmental Science, Faculty of Agriculture, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur, Bangladesh
| | - M Z H Tanvir
- Department of Environmental Science, Faculty of Agriculture, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur, Bangladesh
| | - M M Haque
- Department of Environmental Science, Faculty of Agriculture, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur, Bangladesh
| | - M A Haque
- Department of Agro-Processing, Faculty of Agriculture, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur, Bangladesh
| | - M A A Khan
- Department of Plant Pathology, Faculty of Agriculture, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur, Bangladesh
| | - A H Molla
- Department of Environmental Science, Faculty of Agriculture, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur, Bangladesh
| | - Mohammad Z Alam
- Department of Environmental Science, Faculty of Agriculture, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur, Bangladesh
| | - M S Islam
- Bangladesh Jute Research Institute, Dhaka, Bangladesh
| | - M R Talukder
- Department of Environmental Science, Faculty of Agriculture, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur, Bangladesh
| |
Collapse
|
35
|
Martins PMM, Merfa MV, Takita MA, De Souza AA. Persistence in Phytopathogenic Bacteria: Do We Know Enough? Front Microbiol 2018; 9:1099. [PMID: 29887856 PMCID: PMC5981161 DOI: 10.3389/fmicb.2018.01099] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 05/08/2018] [Indexed: 01/05/2023] Open
Abstract
Phytopathogenic bacteria affect a wide range of crops worldwide and have a negative impact in agriculture due to their associated economic losses and environmental impacts. Together with other biotic and abiotic stress factors, they pose a threat to global food production. Therefore, understanding bacterial survival strategies is an essential step toward the development of new strategies to control plant diseases. One mechanism used by bacteria to survive under stress conditions is the formation of persister cells. Persisters are a small fraction of phenotypic variants within an isogenic population that exhibits multidrug tolerance without undergoing genetic changes. They are dormant cells that survive treatment with antimicrobials by inactivating the metabolic functions that are disrupted by these compounds. They are thus responsible for the recalcitrance of many human diseases, and in the same way, they are thought to contribute to the survival of bacterial phytopathogens under a range of stresses they face in the environment. It is believed that persister cells of bacterial phytopathogens may lead to the reoccurrence of disease by recovering growth and recolonizing the host plant after the end of stress. However, compared to human pathogens, little is known about persister cells in phytopathogens, especially about their genetic regulation. In this review, we describe the overall knowledge on persister cells and their regulation in bacterial phytopathogens, focusing on their ability to survive stress conditions, to recover from dormancy and to maintain virulence.
Collapse
Affiliation(s)
- Paula M. M. Martins
- Laboratório de Biotecnologia, Centro de Citricultura, Instituto Agronômico de Campinas, Cordeiropolis, Brazil
| | - Marcus V. Merfa
- Department of Entomology and Plant Pathology, Auburn University, Auburn, AL, United States
| | - Marco A. Takita
- Laboratório de Biotecnologia, Centro de Citricultura, Instituto Agronômico de Campinas, Cordeiropolis, Brazil
| | - Alessandra A. De Souza
- Laboratório de Biotecnologia, Centro de Citricultura, Instituto Agronômico de Campinas, Cordeiropolis, Brazil
| |
Collapse
|
36
|
Chen H, Kandel PP, Cruz LF, Cobine PA, De La Fuente L. The Major Outer Membrane Protein MopB Is Required for Twitching Movement and Affects Biofilm Formation and Virulence in Two Xylella fastidiosa strains. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2017; 30:896-905. [PMID: 28800709 DOI: 10.1094/mpmi-07-17-0161-r] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
MopB is a major outer membrane protein (OMP) in Xylella fastidiosa, a bacterial plant pathogen that causes losses on many economically important crops. Based on in silico analysis, the uncharacterized MopB protein of X. fastidiosa contains a β-barrel structure with an OmpA-like domain and a predicted calcium-binding motif. Here, MopB function was studied by mutational analysis taking advantage of the natural competence of X. fastidiosa. Mutants of mopB were constructed in two different X. fastidiosa strains, the type strain Temecula and the more virulent WM1-1. Deletion of the mopB gene impaired cell-to-cell aggregation, surface attachment, and biofilm formation in both strains. Interestingly, mopB deletion completely abolished twitching motility. Electron microscopy of the bacterial cell surface revealed that mopB deletion eliminated type IV and type I pili formation, potentially caused by destabilization of the outer membrane. Both mopB mutants showed reduced virulence using tobacco (Nicotiana tabacum) as a host under greenhouse conditions. These results suggest that MopB has pleiotropic functions in biofilm formation and twitching motility and is important for virulence of X. fastidiosa.
Collapse
Affiliation(s)
- Hongyu Chen
- 1 Department of Entomology and Plant Pathology, Auburn University, Auburn, AL 36849, U.S.A.; and
| | - Prem P Kandel
- 1 Department of Entomology and Plant Pathology, Auburn University, Auburn, AL 36849, U.S.A.; and
| | - Luisa F Cruz
- 1 Department of Entomology and Plant Pathology, Auburn University, Auburn, AL 36849, U.S.A.; and
| | - Paul A Cobine
- 2 Department of Biological Sciences, Auburn University
| | - Leonardo De La Fuente
- 1 Department of Entomology and Plant Pathology, Auburn University, Auburn, AL 36849, U.S.A.; and
| |
Collapse
|
37
|
Poole K. At the Nexus of Antibiotics and Metals: The Impact of Cu and Zn on Antibiotic Activity and Resistance. Trends Microbiol 2017; 25:820-832. [PMID: 28526548 DOI: 10.1016/j.tim.2017.04.010] [Citation(s) in RCA: 183] [Impact Index Per Article: 26.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Revised: 04/18/2017] [Accepted: 04/26/2017] [Indexed: 12/14/2022]
Abstract
Environmental influences on antibiotic activity and resistance can wreak havoc with in vivo antibiotic efficacy and, ultimately, antimicrobial chemotherapy. In nature, bacteria encounter a variety of metal ions, particularly copper (Cu) and zinc (Zn), as contaminants in soil and water, as feed additives in agriculture, as clinically-used antimicrobials, and as components of human antibacterial responses. Importantly, there is a growing body of evidence for Cu/Zn driving antibiotic resistance development in metal-exposed bacteria, owing to metal selection of genetic elements harbouring both metal and antibiotic resistance genes, and metal recruitment of antibiotic resistance mechanisms. Many classes of antibiotics also form complexes with metal cations, including Cu and Zn, and this can hinder (or enhance) antibiotic activity. This review highlights the ways in which Cu/Zn influence antibiotic resistance development and antibiotic activity, and in so doing impact in vivo antibiotic efficacy.
Collapse
Affiliation(s)
- Keith Poole
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada, K7L 3N6.
| |
Collapse
|
38
|
Redmile-Gordon M, Chen L. Zinc toxicity stimulates microbial production of extracellular polymers in a copiotrophic acid soil. INTERNATIONAL BIODETERIORATION & BIODEGRADATION 2017; 119:413-418. [PMID: 28413265 PMCID: PMC5380658 DOI: 10.1016/j.ibiod.2016.10.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Revised: 10/01/2016] [Accepted: 10/03/2016] [Indexed: 05/27/2023]
Abstract
The production of extracellular polymeric substances (EPS) is crucial for biofilm structure, microbial nutrition and proximal stability of habitat in a variety of environments. However, the production patterns of microbial EPS in soils as affected by heavy metal contamination remain uncertain. Here we investigate the extracellular response of the native microbial biomass in a grassland soil treated with refined glycerol or crude unrefined biodiesel co-product (BCP) with and without ZnCl2. We extracted microbial EPS and more readily soluble microbial products (SMP), and quantified total polysaccharide, uronic acid, and protein content in these respective extracts. Organic addition, especially BCP, significantly stimulated the production of EPS-polysaccharide and protein but had no impact on EPS-uronic acids, while in the SMP-fraction, polysaccharides and uronic acids were both significantly increased. In response to the inclusion of Zn2+, both EPS- and SMP-polysaccharides increased. This implies firstly that a tolerance mechanism of soil microorganisms against Zn2+ toxicity exists through the stimulation of SMP and EPS production, and secondly that co-products of biofuel industries may have value-added use in bioremediation efforts to support in-situ production of microbial biopolymers. Microbial films and mobile polymers are likely to impact a range of soil properties. The recent focus on EPS research in soils is anticipated to help contribute an improved understanding of biofilm dynamics in other complex systems - such as continuously operated bioreactors.
Collapse
Affiliation(s)
- Marc Redmile-Gordon
- Department of Sustainable Soils and Grassland Systems, Rothamsted Research, Harpenden, Herts AL5 2JQ, UK
| | - Lin Chen
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
- Institute of Soil and Water Resources and Environmental Science, Zhejiang University, Hangzhou 310058, China
| |
Collapse
|
39
|
Chandrangsu P, Helmann JD. Intracellular Zn(II) Intoxication Leads to Dysregulation of the PerR Regulon Resulting in Heme Toxicity in Bacillus subtilis. PLoS Genet 2016; 12:e1006515. [PMID: 27935957 PMCID: PMC5189952 DOI: 10.1371/journal.pgen.1006515] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Revised: 12/27/2016] [Accepted: 11/30/2016] [Indexed: 12/20/2022] Open
Abstract
Transition metal ions (Zn(II), Cu(II)/(I), Fe(III)/(II), Mn(II)) are essential for life and participate in a wide range of biological functions. Cellular Zn(II) levels must be high enough to ensure that it can perform its essential roles. Yet, since Zn(II) binds to ligands with high avidity, excess Zn(II) can lead to protein mismetallation. The major targets of mismetallation, and the underlying causes of Zn(II) intoxication, are not well understood. Here, we use a forward genetic selection to identify targets of Zn(II) toxicity. In wild-type cells, in which Zn(II) efflux prevents intoxication of the cytoplasm, extracellular Zn(II) inhibits the electron transport chain due to the inactivation of the major aerobic cytochrome oxidase. This toxicity can be ameliorated by depression of an alternate oxidase or by mutations that restrict access of Zn(II) to the cell surface. Conversely, efflux deficient cells are sensitive to low levels of Zn(II) that do not inhibit the respiratory chain. Under these conditions, intracellular Zn(II) accumulates and leads to heme toxicity. Heme accumulation results from dysregulation of the regulon controlled by PerR, a metal-dependent repressor of peroxide stress genes. When metallated with Fe(II) or Mn(II), PerR represses both heme biosynthesis (hemAXCDBL operon) and the abundant heme protein catalase (katA). Metallation of PerR with Zn(II) disrupts this coordination, resulting in depression of heme biosynthesis but continued repression of catalase. Our results support a model in which excess heme partitions to the membrane and undergoes redox cycling catalyzed by reduced menaquinone thereby resulting in oxidative stress.
Collapse
Affiliation(s)
- Pete Chandrangsu
- Department of Microbiology, Cornell University, Ithaca, New York, United States of America
| | - John D. Helmann
- Department of Microbiology, Cornell University, Ithaca, New York, United States of America
- * E-mail:
| |
Collapse
|
40
|
Jeger M, Bragard C, Caffier D, Chatzivassiliou E, Dehnen-Schmutz K, Gilioli G, Grégoire JC, Jaques Miret JA, MacLeod A, Navajas Navarro M, Niere B, Parnell S, Potting R, Rafoss T, Rossi V, Urek G, Van Bruggen A, Van Der Werf W, West J, Winter S, De La Fuente L, Spotti Lopes JR, Tramontini S, Andueza M, Candresse T. Susceptibility of Citrusspp., Quercus ilexand Vitisspp. to Xylella fastidiosastrain CoDiRO. EFSA J 2016. [DOI: 10.2903/j.efsa.2016.4601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
|
41
|
Kandel PP, Lopez SM, Almeida RPP, De La Fuente L. Natural Competence of Xylella fastidiosa Occurs at a High Frequency Inside Microfluidic Chambers Mimicking the Bacterium's Natural Habitats. Appl Environ Microbiol 2016; 82:5269-77. [PMID: 27316962 PMCID: PMC4988197 DOI: 10.1128/aem.01412-16] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Accepted: 06/13/2016] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED Xylella fastidiosa is a xylem-limited bacterium that is the causal agent of emerging diseases in a number of economically important crops. Genetic diversity studies have demonstrated homologous recombination occurring among X. fastidiosa strains, which has been proposed to contribute to host plant shifts. Moreover, experimental evidence confirmed that X. fastidiosa is naturally competent for recombination in vitro Here, as an approximation of natural habitats (plant xylem vessels and insect mouthparts), recombination was studied in microfluidic chambers (MCs) filled with media amended with grapevine xylem sap. First, different media were screened for recombination in solid agar plates using a pair of X. fastidiosa strains that were previously reported to recombine in coculture. The highest frequency of recombination was obtained with PD3 medium, compared to those with the other two media (X. fastidiosa medium [XFM] and periwinkle wilt [PW] medium) used in previous studies. Dissection of the media components led to the identification of bovine serum albumin as an inhibitor of recombination that was correlated to its previously known effect on inhibition of twitching motility. When recombination was performed in liquid culture, the frequencies were significantly higher under flow conditions (MCs) than under batch conditions (test tubes). The recombination frequencies in MCs and agar plates were not significantly different from each other. Grapevine xylem sap from both susceptible and tolerant varieties allowed high recombination frequency in MCs when mixed with PD3. These results suggest that X. fastidiosa has the ability to be naturally competent in the natural growth environment of liquid flow, and this phenomenon could have implications in X. fastidiosa environmental adaptation. IMPORTANCE Xylella fastidiosa is a plant pathogen that lives inside xylem vessels (where water and nutrients are transported inside the plant) and the mouthparts of insect vectors. This bacterium causes emerging diseases in various crops worldwide, including recent outbreaks in Europe. The mechanisms by which this bacterium adapts to new hosts is not understood, but it was previously shown that it is naturally competent, meaning that it can take up DNA from the environment and incorporate it into its genome (recombination). In this study, we show that the frequency of recombination is highest when the bacterium is grown under flow conditions in microfluidic chambers modeled after its natural habitats, and recombination was still high when the medium was amended with grapevine sap. Our results suggest that this bacterium is able to recombine when growing inside plants or insects, and this can be a mechanism of adaptation of this pathogen that causes incurable diseases.
Collapse
Affiliation(s)
- Prem P Kandel
- Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama, USA
| | - Samantha M Lopez
- Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama, USA
| | - Rodrigo P P Almeida
- Department of Environmental Science, Policy and Management, University of California, Berkeley, California, USA
| | - Leonardo De La Fuente
- Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama, USA
| |
Collapse
|
42
|
Merfa MV, Niza B, Takita MA, De Souza AA. The MqsRA Toxin-Antitoxin System from Xylella fastidiosa Plays a Key Role in Bacterial Fitness, Pathogenicity, and Persister Cell Formation. Front Microbiol 2016; 7:904. [PMID: 27375608 PMCID: PMC4901048 DOI: 10.3389/fmicb.2016.00904] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Accepted: 05/26/2016] [Indexed: 01/01/2023] Open
Abstract
Through the formation of persister cells, bacteria exhibit tolerance to multidrug and other environmental stresses without undergoing genetic changes. The toxin-antitoxin (TA) systems are involved in the formation of persister cells because they are able to induce cell dormancy. Among the TA systems, the MqsRA system has been observed to be highly induced in persister cells of Xylella fastidiosa (causal agent of citrus variegated chlorosis-CVC) activated by copper stress, and has been described in Escherichia coli as related to the formation of persister cells and biofilms. Thus, we evaluated the role of this TA system in X. fastidiosa by overexpressing the MqsR toxin, and verified that the toxin positively regulated biofilm formation and negatively cell movement, resulting in reduced pathogenicity in citrus plants. The overexpression of MqsR also increased the formation of persister cells under copper stress. Analysis of the gene and protein expression showed that this system likely has an autoregulation mechanism to express the toxin and antitoxin in the most beneficial ratio for the cell to oppose stress. Our results suggest that this TA system plays a key role in the adaptation and survival of X. fastidiosa and reveal new insights into the physiology of phytopathogen-host interactions.
Collapse
Affiliation(s)
- Marcus V. Merfa
- Instituto Agronômico, Centro de Citricultura Sylvio MoreiraCordeirópolis, Brazil
- Departamento de Genética, Evolução e Bioagentes, Universidade Estadual de CampinasCampinas, Brazil
| | - Bárbara Niza
- Instituto Agronômico, Centro de Citricultura Sylvio MoreiraCordeirópolis, Brazil
- Departamento de Genética, Evolução e Bioagentes, Universidade Estadual de CampinasCampinas, Brazil
| | - Marco A. Takita
- Instituto Agronômico, Centro de Citricultura Sylvio MoreiraCordeirópolis, Brazil
| | | |
Collapse
|
43
|
Espinosa-Ortiz EJ, Pechaud Y, Lauchnor E, Rene ER, Gerlach R, Peyton BM, van Hullebusch ED, Lens PNL. Effect of selenite on the morphology and respiratory activity of Phanerochaete chrysosporium biofilms. BIORESOURCE TECHNOLOGY 2016; 210:138-145. [PMID: 26935326 DOI: 10.1016/j.biortech.2016.02.074] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Revised: 02/16/2016] [Accepted: 02/19/2016] [Indexed: 06/05/2023]
Abstract
The temporal and spatial effects of selenite (SeO3(2-)) on the physical properties and respiratory activity of Phanerochaete chrysosporium biofilms, grown in flow-cell reactors, were investigated using oxygen microsensors and confocal laser scanning microscopy (CLSM) imaging. Exposure of the biofilm to a SeO3(2-) load of 1.67mgSeL(-1)h(-1) (10mgSeL(-1) influent concentration), for 24h, resulted in a 20% reduction of the O2 flux, followed by a ∼10% decrease in the glucose consumption rate. Long-term exposure (4days) to SeO3(2-) influenced the architecture of the biofilm by creating a more compact and dense hyphal arrangement resulting in a decrease of biofilm thickness compared to fungal biofilms grown without SeO3(2-). To the best of our knowledge, this is the first time that the effect of SeO3(2-) on the aerobic respiratory activity on fungal biofilms is described.
Collapse
Affiliation(s)
| | - Yoan Pechaud
- Université Paris-Est, Laboratoire Géomatériaux et Environnement (EA 4508), UPEM, 77454 Marne-la-Vallée, France
| | - Ellen Lauchnor
- Center for Biofilm Engineering, Montana State University, 366 EPS, PO Box 173980, Bozeman, MT 59717, USA
| | - Eldon R Rene
- UNESCO-IHE Institute for Water Education, Westvest 7, 2611 AX Delft, The Netherlands
| | - Robin Gerlach
- Center for Biofilm Engineering, Montana State University, 366 EPS, PO Box 173980, Bozeman, MT 59717, USA
| | - Brent M Peyton
- Center for Biofilm Engineering, Montana State University, 366 EPS, PO Box 173980, Bozeman, MT 59717, USA
| | - Eric D van Hullebusch
- Université Paris-Est, Laboratoire Géomatériaux et Environnement (EA 4508), UPEM, 77454 Marne-la-Vallée, France
| | - Piet N L Lens
- UNESCO-IHE Institute for Water Education, Westvest 7, 2611 AX Delft, The Netherlands
| |
Collapse
|
44
|
|
45
|
Parker JK, Chen H, McCarty SE, Liu LY, De La Fuente L. Calcium transcriptionally regulates the biofilm machinery of Xylella fastidiosa to promote continued biofilm development in batch cultures. Environ Microbiol 2016; 18:1620-34. [PMID: 26913481 DOI: 10.1111/1462-2920.13242] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Accepted: 01/21/2016] [Indexed: 11/29/2022]
Abstract
The functions of calcium (Ca) in bacteria are less characterized than in eukaryotes, where its role has been studied extensively. The plant-pathogenic bacterium Xylella fastidiosa has several virulence features that are enhanced by increased Ca concentrations, including biofilm formation. However, the specific mechanisms driving modulation of this feature are unclear. Characterization of biofilm formation over time showed that 4 mM Ca supplementation produced denser biofilms that were still developing at 96 h, while biofilm in non-supplemented media had reached the dispersal stage by 72 h. To identify changes in global gene expression in X. fastidiosa grown in supplemental Ca, RNA-Seq of batch culture biofilm cells was conducted at three 24-h time intervals. Results indicate that a variety of genes are differentially expressed in response to Ca, including genes related to attachment, motility, exopolysaccharide synthesis, biofilm formation, peptidoglycan synthesis, regulatory functions, iron homeostasis, and phages. Collectively, results demonstrate that Ca supplementation induces a transcriptional response that promotes continued biofilm development, while biofilm cells in nonsupplemented media are driven towards dispersion of cells from the biofilm structure. These results have important implications for disease progression in planta, where xylem sap is the source of Ca and other nutrients for X. fastidiosa.
Collapse
Affiliation(s)
- Jennifer K Parker
- Department of Entomology and Plant Pathology, Auburn University, Auburn, AL
| | - Hongyu Chen
- Department of Entomology and Plant Pathology, Auburn University, Auburn, AL
| | - Sara E McCarty
- Department of Entomology and Plant Pathology, Auburn University, Auburn, AL
| | - Lawrence Y Liu
- Department of Entomology and Plant Pathology, Auburn University, Auburn, AL
| | | |
Collapse
|
46
|
Whidden M, Cogan N, Donahue M, Navarrete F, De La Fuente L. A Two-Dimensional Multiphase Model of Biofilm Formation in Microfluidic Chambers. Bull Math Biol 2015; 77:2161-79. [PMID: 26621357 DOI: 10.1007/s11538-015-0115-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2014] [Accepted: 10/15/2015] [Indexed: 10/22/2022]
Abstract
The bacterial pathogen Xylella fastidiosa is the causal agent of many pathological conditions of economically important agricultural crops. There is no known cure for X. fastidiosa diseases, and management of the problem is based solely in controlling the population of insect vectors, which is somewhat effective. The bacterium causes disease by forming biofilms inside the vascular system of the plant, a process that is poorly understood. In microfluidic chambers, used as artificial xylem vessels, this bacterium has been observed to reproducibly cluster into a distinct, regular pattern of aggregates, spatially separated by channels of non-biofilm components. We develop a multiphase model in two dimensions, which recapitulates this spatial patterning, suggesting that bacterial growth and attachment/detachment processes are strongly influential modulators of these patterns. This indicates plausible strategies, such as the addition of metals and chelators, for mitigating the severity of diseases induced by this bacterial pathogen.
Collapse
Affiliation(s)
- Mark Whidden
- Department of Molecular & Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI, USA.
| | - Nick Cogan
- Department of Mathematics, Florida State University, Tallahassee, FL, USA
| | - Matt Donahue
- Department of Mathematics, University of Tulsa, Tulsa, OK, USA
| | - Fernando Navarrete
- Department of Entomology and Plant Pathology, Auburn University, Auburn, AL, USA
| | | |
Collapse
|
47
|
|
48
|
Janissen R, Murillo DM, Niza B, Sahoo PK, Nobrega MM, Cesar CL, Temperini MLA, Carvalho HF, de Souza AA, Cotta MA. Spatiotemporal distribution of different extracellular polymeric substances and filamentation mediate Xylella fastidiosa adhesion and biofilm formation. Sci Rep 2015; 5:9856. [PMID: 25891045 PMCID: PMC4402645 DOI: 10.1038/srep09856] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2014] [Accepted: 03/20/2015] [Indexed: 12/30/2022] Open
Abstract
Microorganism pathogenicity strongly relies on the generation of multicellular assemblies, called biofilms. Understanding their organization can unveil vulnerabilities leading to potential treatments; spatially and temporally-resolved comprehensive experimental characterization can provide new details of biofilm formation, and possibly new targets for disease control. Here, biofilm formation of economically important phytopathogen Xylella fastidiosa was analyzed at single-cell resolution using nanometer-resolution spectro-microscopy techniques, addressing the role of different types of extracellular polymeric substances (EPS) at each stage of the entire bacterial life cycle. Single cell adhesion is caused by unspecific electrostatic interactions through proteins at the cell polar region, where EPS accumulation is required for more firmly-attached, irreversibly adhered cells. Subsequently, bacteria form clusters, which are embedded in secreted loosely-bound EPS, and bridged by up to ten-fold elongated cells that form the biofilm framework. During biofilm maturation, soluble EPS forms a filamentous matrix that facilitates cell adhesion and provides mechanical support, while the biofilm keeps anchored by few cells. This floating architecture maximizes nutrient distribution while allowing detachment upon larger shear stresses; it thus complies with biological requirements of the bacteria life cycle. Using new approaches, our findings provide insights regarding different aspects of the adhesion process of X. fastidiosa and biofilm formation.
Collapse
Affiliation(s)
- Richard Janissen
- Applied Physics Department, Institute of Physics ‘Gleb Wataghin’, State University of Campinas, 13083-859, Campinas, São Paulo, Brazil
| | - Duber M. Murillo
- Applied Physics Department, Institute of Physics ‘Gleb Wataghin’, State University of Campinas, 13083-859, Campinas, São Paulo, Brazil
| | - Barbara Niza
- Citrus Center APTA ‘Sylvio Moreira’, Agronomic Institute of Campinas, 13490-970, Cordeirópolis, São Paulo, Brazil
| | - Prasana K. Sahoo
- Applied Physics Department, Institute of Physics ‘Gleb Wataghin’, State University of Campinas, 13083-859, Campinas, São Paulo, Brazil
| | - Marcelo M. Nobrega
- Fundamental Chemistry Department, Institute of Chemistry, University of São Paulo, 05508-000, São Paulo, Brazil
| | - Carlos L. Cesar
- Quantum Electronics Department, Institute of Physics ‘Gleb Wataghin’, State University of Campinas, 13083-859, Campinas, São Paulo, Brazil
| | - Marcia L. A. Temperini
- Fundamental Chemistry Department, Institute of Chemistry, University of São Paulo, 05508-000, São Paulo, Brazil
| | - Hernandes F. Carvalho
- Structural and Functional Biology Department, Institute of Biology, State University of Campinas, 13083-865, Campinas, São Paulo, Brazil
| | - Alessandra A. de Souza
- Citrus Center APTA ‘Sylvio Moreira’, Agronomic Institute of Campinas, 13490-970, Cordeirópolis, São Paulo, Brazil
| | - Monica A. Cotta
- Applied Physics Department, Institute of Physics ‘Gleb Wataghin’, State University of Campinas, 13083-859, Campinas, São Paulo, Brazil
| |
Collapse
|
49
|
Toxic metal resistance in biofilms: diversity of microbial responses and their evolution. Res Microbiol 2015; 166:764-73. [PMID: 25869223 DOI: 10.1016/j.resmic.2015.03.008] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Revised: 03/23/2015] [Accepted: 03/25/2015] [Indexed: 11/20/2022]
Abstract
Since biofilms are an important issue in the fields of medicine and health, several recent microbiological studies have focused on their formation and their contribution to toxic compound resistance mechanisms. In this review, we describe how metals impact biofilm formation and resistance, and how biofilms can help cells resist toxic metals. First, the organic matrix acts as a barrier isolating the cells from many environmental stresses. Secondly, the metabolism of the cells changes, and a slowly-growing or non-growing sub-population of cells known as persisters emerges. Thirdly, in the case of multispecies biofilms, metabolic interactions are developed, allowing cells to be more persistent or to have greater capacity to survive than a single species biofilm. Finally, we discuss how the high density of the cells may promote horizontal gene transfer processes, resulting in the acquisition of new features. All these crucial mechanisms enable microorganisms to survive and colonize toxic environments, and probably accelerate ongoing evolutionary processes.
Collapse
|
50
|
Navarrete F, De La Fuente L. Zinc Detoxification Is Required for Full Virulence and Modification of the Host Leaf Ionome by Xylella fastidiosa. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2015; 28:497-507. [PMID: 25561271 DOI: 10.1094/mpmi-07-14-0221-r] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Zinc (Zn) is an essential element for all forms of life because it is a structural or catalytic cofactor of many proteins, but it can have toxic effects at high concentrations; thus, microorganisms must tightly regulate its levels. Here, we evaluated the role of Zn homeostasis proteins in the virulence of the xylem-limited bacterium Xylella fastidiosa, causal agent of Pierce's disease of grapevine, among other diseases. Two mutants of X. fastidiosa 'Temecula' affected in genes which regulate Zn homeostasis (zur) and Zn detoxification (czcD) were constructed. Both knockouts showed increased sensitivity to Zn at physiologically relevant concentrations and increased intracellular accumulation of this metal compared with the wild type. Increased Zn sensitivity was correlated with decreased growth in grapevine xylem sap, reduced twitching motility, and downregulation of exopolysaccharide biosynthetic genes. Tobacco plants inoculated with either knockout mutant showed reduced foliar symptoms and a much reduced (czcD) or absent (zur) modification of the leaf ionome (i.e., the mineral nutrient and trace element composition), as well as reduced bacterial populations. The results show that detoxification of Zn is crucial for the virulence of X. fastidiosa and verifies our previous findings that modification of the host leaf ionome correlates with bacterial virulence.
Collapse
Affiliation(s)
- Fernando Navarrete
- Department of Entomology and Plant Pathology, Auburn University, Auburn, AL 36849, U.S.A
| | | |
Collapse
|