scholarly journals Fusarium verticillioides: Advancements in Understanding the Toxicity, Virulence, and Niche Adaptations of a Model Mycotoxigenic Pathogen of Maize

2018 ◽  
Vol 108 (3) ◽  
pp. 312-326 ◽  
Author(s):  
Alex A. Blacutt ◽  
Scott E. Gold ◽  
Kenneth A. Voss ◽  
Minglu Gao ◽  
Anthony E. Glenn
Keyword(s):  
Secondary Metabolites ◽  
Current Knowledge ◽  
Fusarium Verticillioides ◽  
Animal Health ◽  
Disease Outbreaks ◽  
Toxin Production ◽  
Economic Returns ◽  
Plant Host ◽  
Host Interactions ◽  
Basic And Applied Research

The importance of understanding the biology of the mycotoxigenic fungus Fusarium verticillioides and its various microbial and plant host interactions is critical given its threat to maize, one of the world’s most valuable food crops. Disease outbreaks and mycotoxin contamination of grain threaten economic returns and have grave implications for human and animal health and food security. Furthermore, F. verticillioides is a member of a genus of significant phytopathogens and, thus, data regarding its host association, biosynthesis of secondary metabolites, and other metabolic (degradative) capabilities are consequential to both basic and applied research efforts across multiple pathosystems. Notorious among its secondary metabolites are the fumonisin mycotoxins, which cause severe animal diseases and are implicated in human disease. Additionally, studies of these mycotoxins have led to new understandings of F. verticillioides plant pathogenicity and provide tools for research into cellular processes and host–pathogen interaction strategies. This review presents current knowledge regarding several significant lines of F. verticillioides research, including facets of toxin production, virulence, and novel fitness strategies exhibited by this fungus across rhizosphere and plant environments.

scholarly journals Feedborne Mycotoxins Beauvericin and Enniatins and Livestock Animals

Toxins ◽  
2021 ◽  
Vol 13 (1) ◽  
pp. 32
Author(s):  
Ludmila Křížová ◽  
Kateřina Dadáková ◽  
Michaela Dvořáčková ◽  
Tomáš Kašparovský
Keyword(s):  
Secondary Metabolites ◽  
Current Knowledge ◽  
Biological Activities ◽  
Animal Health ◽  
Cereal Grains ◽  
Animal Tissues ◽  
Penicillium Species ◽  
And Performance ◽  
Carry Over

Mycotoxins are secondary metabolites produced by several species of fungi, including the Fusarium, Aspergillus, and Penicillium species. Currently, more than 300 structurally diverse mycotoxins are known, including a group called minor mycotoxins, namely enniatins, beauvericin, and fusaproliferin. Beauvericin and enniatins possess a variety of biological activities. Their antimicrobial, antibiotic, or ionoforic activities have been proven and according to various bioassays, they are believed to be toxic. They are mainly found in cereal grains and their products, but they have also been detected in forage feedstuff. Mycotoxins in feedstuffs of livestock animals are of dual concern. First one relates to the safety of animal-derived food. Based on the available data, the carry-over of minor mycotoxins from feed to edible animal tissues is possible. The second concern relates to detrimental effects of mycotoxins on animal health and performance. This review aims to summarize current knowledge on the relation of minor mycotoxins to livestock animals.

scholarly journals The cAMP Signaling Pathway in Fusarium verticillioides Is Important for Conidiation, Plant Infection, and Stress Responses but Not Fumonisin Production

2010 ◽  
Vol 23 (4) ◽  
pp. 522-533 ◽  
Author(s):  
Yoon-E Choi ◽  
Jin-Rong Xu
Keyword(s):  
Stress Responses ◽  
Fungal Pathogens ◽  
Fusarium Verticillioides ◽  
Animal Health ◽  
Toxin Production ◽  
Catalytic Subunit ◽  
Camp Signaling ◽  
Deletion Mutants ◽  
Plant Infection ◽  
Pka Pathway

Fusarium verticillioides is one of the most important fungal pathogens of maize. Mycotoxin, fumonisins produced by this pathogen pose a threat to human and animal health. Because cAMP signaling has been implicated in regulating diverse developmental and infection processes in fungal pathogens, in this study, we aimed to elucidate the function of the cAMP–protein kinase A (PKA) pathway in toxin production and plant infection in F. verticillioides. Targeted deletion mutants were generated for the CPK1 and FAC1 genes that encode a catalytic subunit of PKA and the adenylate cyclase, respectively. Defects in radial growth and macroconidiation were observed in both the cpk1 and fac1 deletion mutants. The fac1 mutant also was significantly reduced in virulence and microconidiation but increased in tolerance to heat and oxidative stresses. These phenotypes were not observed in the cpk1 mutant, indicating that additional catalytic subunit of PKA must exist and function downstream from FAC1. The fac1 mutant formed microconidia mainly in false heads. The expression levels of the hydrophobin genes HYD1 and HYD2, which are known to be associated with change in formation of microconidia, were significantly reduced in the fac1 mutant. Expression of F. verticillioides GSY2 and HSP26 genes, two other putative downstream targets of FAC1, was increased in the fac1 mutant and may be associated with its enhanced stress tolerance. Although fumonisin production was normal, biosynthesis of bikaverin was increased in the fac1 mutant, suggesting that FAC1 and cAMP signaling may have pathway-or metabolite-specific regulatory roles in secondary metabolism. Overall, the pleiotropic defects of the fac1 deletion mutant indicate that the cAMP-PKA pathway is involved in growth, conidiation, bikaverin production, and plant infection in F. verticillioides.

scholarly journals Holoparasitic Plant–Host Interactions and their Impact on Mediterranean Ecosystems

2021 ◽  
Author(s):  
Andrea Casadesús ◽  
Sergi Munné-Bosch
Keyword(s):  
Current Knowledge ◽  
Abiotic Factors ◽  
Biological Significance ◽  
Mediterranean Ecosystems ◽  
Natural Ecosystems ◽  
Plant Host ◽  
Host Interactions ◽  
Holoparasitic Plants ◽  
Holoparasitic Plant ◽  
The Impact

Abstract Although photosynthesis is essential to sustain life on Earth, not all plants use sunlight to synthesize nutrients from carbon dioxide and water. Holoparasitic plants, which are important in agricultural and natural ecosystems, are dependent on other plants for nutrients. Phytohormones are crucial in holoparasitic plant–host interactions, from seed germination to senescence, not only because they act as growth and developmental regulators, but also because of their central role in the regulation of host photosynthesis and source–sink relations between the host and the holoparasitic plant. Here, we compile and discuss current knowledge on the impact and ecophysiology of holoparasitic plants (such as the broomrapes Orobanche sp. and Phelipanche sp.) that infest economically important dicotyledonous crops in Mediterranean agroecosystems (legumes [Fabaceae], sunflowers [Helianthus sp.] or tomato [Solanum lycopersicum] plants). We also highlight the role of holoparasitic plant–host interactions (such as those between Cytinus hypocistis and various shrubs of the genus Cistus) in shaping natural Mediterranean ecosystems. The roles of phytohormones in controlling plant–host interactions, abiotic factors in parasitism, and the biological significance of natural seed banks and how dormancy and germination are regulated, will all be discussed. Holoparasitic plants are unique organisms; improving our understanding of their interaction with hosts as study models will help us to better manage parasitic plants, both in agricultural and natural ecosystems.

scholarly journals lmportancia de los metabolitos secundarios de plantas y hongos en las enfermedades de las planta.

2001 ◽  
Vol 3 (2) ◽  
pp. 24
Author(s):  
Aníbal L. Tapiero
Keyword(s):  
Secondary Metabolites ◽  
Plant Disease ◽  
Secondary Compounds ◽  
Plant Diseases ◽  
Target Cells ◽  
Plant Host ◽  
Host Interactions ◽  
Fungal Plant Disease ◽  
Potential Pathogen ◽  
Infection Processes

<p>Los procesos que siguen al encuentro de un hongo fitopatógeno con su hospedero potencial son extraordinariamente complejos. Las especies fuera del rango de hospederos deben ser descartadas inmediatamente y los hospederos potenciales deben ser escogidos coincidiendo con el correcto estado de desarrollo durante el cual éstos son vulnerables. Independientemente del hábito de crecimiento del patógeno (necrotrófico o biotrófico), el proceso de infección debe ser operado con base en el tiempo. La germinación y el desarrollo de las unidades infectivas mientras el hospedero está desplegando sus mecanismos de defensa llevarían al patógeno a su desaparición. De alguna manera, la unidad infectiva del patógeno debe reconocer a su hospedero, eludir las barreras iniciales de defensa e iniciar el proceso de infección. Las condiciones ambientales juegan un papel importante durante el intercambio hospedero-patógeno. La germinación de la unidad infectiva es determinada por el ambiente y debe coincidir con el momento más adecuado para alcanzar el sitio de penetración. El proceso ulterior induce un delicado sistema de intercambio de señales físicas y químicas entre la unidad de germinación y la epidermis del hospedero potencial. Una vez ocurrida la penetración, el patógeno procede a ubicar las vías y a desarrollar los medios adecuados para llegar hasta las células apropiadas para su desarrollo; bien sea disolviendo enzimáticamente la pared celular del tejido del hospedero o generando la turgencia necesaria para penetrar la epidermis, el patógeno se disemina intra o extracelularmente hasta alcanzar las células de donde derivará su sustento, causando la infección. Durante el proceso de infección, el hospedero desplegará mecanismos pasivos y activos de defensa. Mecanismos pasivos como barreras físicas o configuraciones especializadas en el tejido epidermal, o la presencia de compuestos fito-patogénicos en las células sujetas a la invasión son comunes entre las plantas. Respuestas activas incluyen la producción de sustancias fungi-tóxicas al encuentro con patógenos Potenciales, producto de metabolismos primarios y secundarios. Se han estudiado diferentes compuestos desarrollados tanto para el ataque del patógeno, como para la defensa del hospedero. Algunos de ellos son únicos entre ciertos géneros, especies, variedades, formas y aún cepas específicas en plantas y hongos. El hecho de no ser esenciales para la vida de las plantas y de los hongos en general, les ha valido su denominación de secundarios. Su extraordinario papel en el conjunto de procesos que gobiernan las relaciones hospedero-patógeno ha sido demostrada en varios sistemas en particular y esta revisión se propone, con ejemplos, demostrar su importancia para el mejor entendimiento de las enfermedades de las plantas.</p><p> </p><p><strong>Importance of Plant and Fungal Secondary Metabolites in Plant Diseases.</strong></p><p>The processes that follow the encounter of a fungal pathogen with a potential plant host are remarkably complex. Non-hosts must be discarded at once and hosts must be chosen carefully at the stage they are vulnerable to attack. Whether the invader is a necrotroph or a biotroph, these actions must be performed on a timely basis. While the targeted host is displaying defensive strategies, germinating and developing the subsequent structures for infection will cos the potential pathogen to fail. Somehow the infective units must recognize its host, avoid the initial defensive barriers and start developing the appropriate infection processes. Environmental factors seem to play a definitive role in the interplay, not only by providing the general conditions for germination, but also by doing so at the adequate time. Once the infection unit germinates, the following task is to encounter a site for penetration and this usually involves a delicate physical and chemical signaling process between the germination unit and the host epidermis After penetration, the invader must find ways to reach the target cells, either by dissolving the host cell wall or by developing structures to further invade and spread within the host tissue; then the pathogen reaches the site where nutrients are stored to establish firmly originating the disease. On the other hand the host passively or actively displays mechanisms of defense. Passive mechanisms like physical barriers or pre-formed compounds are common to plants. Active mechanisms, like the turning up of normal and secondary biosynthetic processes to counterattack the invader, are also observed. Different compounds, for attacking as well as for defending, are also found. Some of them are unique to genera, species, varieties, forms and even strains of plants and/or fungi. Regarded as not common to all organism (not necessary for life) these are "secondary" compounds, but only in the sense of distinguishing them from the otherwise common "primary" metabolites. The role of secondary metabolites in pathogen-host interactions has been proved remarkably for several fungal plant disease .The purpose of this review is to describe and present some examples pertaining to their importance for plant disease.</p>

scholarly journals Increasing risks for emerging infectious diseases within a rapidly changing High Asia

AMBIO ◽  
2021 ◽  
Author(s):  
Charudutt Mishra ◽  
Gustaf Samelius ◽  
Munib Khanyari ◽  
Prashanth Nuggehalli Srinivas ◽  
Matthew Low ◽  
...  
Keyword(s):  
Infectious Diseases ◽  
Disease Surveillance ◽  
Current Knowledge ◽  
Animal Health ◽  
Emerging Infectious Diseases ◽  
Disease Outbreaks ◽  
Global Risk ◽  
Disease Surveillance System ◽  
High Asia ◽  
Ecologically Sustainable

AbstractThe cold and arid mountains and plateaus of High Asia, inhabited by a relatively sparse human population, a high density of livestock, and wildlife such as the iconic snow leopard Panthera uncia, are usually considered low risk for disease outbreaks. However, based on current knowledge about drivers of disease emergence, we show that High Asia is rapidly developing conditions that favor increased emergence of infectious diseases and zoonoses. This is because of the existing prevalence of potentially serious pathogens in the system; intensifying environmental degradation; rapid changes in local ecological, socio-ecological, and socio-economic factors; and global risk intensifiers such as climate change and globalization. To better understand and manage the risks posed by diseases to humans, livestock, and wildlife, there is an urgent need for establishing a disease surveillance system and improving human and animal health care. Public health must be integrated with conservation programs, more ecologically sustainable development efforts and long-term disease surveillance.

scholarly journals Examining local perspectives on the influence of climate change on the health of Hamer pastoralists and their livestock in Ethiopia

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Samuel Lumborg ◽  
Samuel Tefera ◽  
Barry Munslow ◽  
Siobhan M. Mor
Keyword(s):  
Climate Change ◽  
Water Scarcity ◽  
Health Workers ◽  
Animal Health ◽  
Disease Outbreaks ◽  
Vulnerable Groups ◽  
Local Health ◽  
Framework Analysis ◽  
Healthcare Facilities ◽  
Grazing Lands

AbstractThis study explores the perceived influence of climate change on the health of Hamer pastoralists and their livestock in south-western Ethiopia. A combination of focus group discussions and key informant interviews were conducted with Hamer communities as well as local health workers, animal health workers and non-governmental organisation (NGO) staff. Thematic framework analysis was used to analyse the data. Reductions in rangeland, erratic rainfall, recurrent droughts and loss of seasonality were perceived to be the biggest climate challenges influencing the health and livelihoods of the Hamer. Communities were travelling greater distances to access sufficient grazing lands, and this was leading to livestock deaths and increases in ethnic violence. Reductions in suitable rangeland were also precipitating disease outbreaks in animals due to increased mixing of different herds. Negative health impacts in the community stemmed indirectly from decreases in livestock production, uncertain crop harvests and increased water scarcity. The remoteness of grazing lands has resulted in decreased availability of animal milk, contributing to malnutrition in vulnerable groups, including children. Water scarcity in the region has led to utilisation of unsafe water sources resulting in diarrhoeal illnesses. Further, seasonal shifts in climate-sensitive diseases such as malaria were also acknowledged. Poorly resourced healthcare facilities with limited accessibility combined with an absence of health education has amplified the community’s vulnerability to health challenges. The resilience and ambition for livelihood diversification amongst the Hamer was evident. The introduction of camels, increase in permanent settlements and new commercial ideas were transforming their livelihood strategies. However, the Hamer lack a voice to express their perspectives, challenges and ambitions. There needs to be collaborative dynamic dialogue between pastoral communities and the policy-makers to drive sustainable development in the area without compromising the values, traditions and knowledge of the pastoralists.

A proposal to leverage high-quality veterinary diagnostic laboratory large data streams for animal health, public health, and One Health

2021 ◽  
pp. 104063872110030
Author(s):  
Craig N. Carter ◽  
Jacqueline L. Smith
Keyword(s):  
Public Health ◽  
Data Streams ◽  
One Health ◽  
Animal Health ◽  
Disease Outbreaks ◽  
Large Data ◽  
Health Impact ◽  
The United States ◽  
Zoonotic Diseases ◽  
Diagnostic Laboratory

Test data generated by ~60 accredited member laboratories of the American Association of Veterinary Laboratory Diagnosticians (AAVLD) is of exceptional quality. These data are captured by 1 of 13 laboratory information management systems (LIMSs) developed specifically for veterinary diagnostic laboratories (VDLs). Beginning ~2000, the National Animal Health Laboratory Network (NAHLN) developed an electronic messaging system for LIMS to automatically send standardized data streams for 14 select agents to a national repository. This messaging enables the U.S. Department of Agriculture to track and respond to high-consequence animal disease outbreaks such as highly pathogenic avian influenza. Because of the lack of standardized data collection in the LIMSs used at VDLs, there is, to date, no means of summarizing VDL large data streams for multi-state and national animal health studies or for providing near-real-time tracking for hundreds of other important animal diseases in the United States that are detected routinely by VDLs. Further, VDLs are the only state and federal resources that can provide early detection and identification of endemic and emerging zoonotic diseases. Zoonotic diseases are estimated to be responsible for 2.5 billion cases of human illness and 2.7 million deaths worldwide every year. The economic and health impact of the SARS-CoV-2 pandemic is self-evident. We review here the history and progress of data management in VDLs and discuss ways of seizing unexplored opportunities to advance data leveraging to better serve animal health, public health, and One Health.

Insects as vectors of foodborne pathogenic bacteria

2011 ◽  
Vol 4 (1) ◽  
pp. 5-16 ◽  
Author(s):  
Jeffrey Blazar ◽  
Marc Allard ◽  
E. Kurt Lienau
Keyword(s):  
Food Safety ◽  
Foodborne Pathogens ◽  
Pathogenic Bacteria ◽  
Current Knowledge ◽  
Disease Outbreaks ◽  
House Fly ◽  
American Cockroach ◽  
Health Concern ◽  
Foodborne Disease ◽  
Salmonella Spp

AbstractFood safety is an important consideration worldwide. To maintain and improve our current knowledge of foodborne disease outbreaks, we must understand some of the more imminent issues related to food safety. A variety of agents are responsible for transmitting the estimated 76 million cases of illnesses caused by foodborne pathogens every year. This review explores why insects pose a serious health concern, in terms of worldwide food safety initiatives, by looking at evidence in published <abs>Food safety is an important consideration worldwide. To maintain and improve our current knowledge of foodborne disease outbreaks, we must understand some of the more imminent issues related to food safety. A variety of agents are responsible for transmitting the estimated 76 million cases of illnesses caused by foodborne pathogens every year. This review explores why insects pose a serious health concern, in terms of worldwide food safety initiatives, by looking at evidence in published literature. We highlight at least eleven different species of insects, including the lesser mealworm, Alphitobius diaperinus (Panzer); secondary screwworm, Cochliomyia macellaria (Fabricius); synanthropic flies [flesh fly, Sarcophaga carnaria (L.); house fly, Musca domestica (L.); fruit fly, Drosophila melanogaster (Meigen); and stable fly, Stomoxys calcitrans (L.)], American cockroach, Periplaneta americana (L.); German cockroach, Blatella germanica (L.); Oriental cockroach, Blatta orientalis (L.); Pacific beetle cockroach, Diploptera punctata (Eschscholtz); and Speckled feeder cockroach, Nauphoeta cinerea (Olivier), which act as vectors for Salmonella spp. or Escherichia coli and illustrate how these insects are successful vectors of foodborne disease outbreaks. We propose that insects be considered as one of the latest issues in food safety initiatives. Not only are some insects extremely important contributors to diseases, but now we suggest that more research into insects as potential carriers of E. coli and Salmonella spp., and therefore as contributing to foodborne disease outbreaks, is granted.

scholarly journals Severe acute respiratory syndrome (SARS) related coronavirus in bats

2021 ◽  
Vol 1 (1) ◽  
Author(s):  
Rong Geng ◽  
Peng Zhou
Keyword(s):  
Severe Acute Respiratory Syndrome ◽  
Current Knowledge ◽  
Disease Outbreaks ◽  
First Century ◽  
Intermediate Hosts ◽  
Human Coronavirus ◽  
Transmission Potential ◽  
Disease Agent ◽  
And Control ◽  
Genomic Similarity

AbstractThree major human coronavirus disease outbreaks, severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS) and 2019 coronavirus disease (COVID-19), occurred in the twenty-first century and were caused by different coronaviruses (CoVs). All these viruses are considered to have originated from bats and transmitted to humans through intermediate hosts. SARS-CoV-1 and SARS-CoV-2, disease agent of COVID-19, shared around 80% genomic similarity, and thus belong to SARS-related CoVs. As a natural reservoir of viruses, bats harbor numerous other SARS-related CoVs that could potentially infect humans around the world, causing SARS or COVID-19 like outbreaks in the future. In this review, we summarized the current knowledge of CoVs on geographical distribution, genetic diversity, cross-species transmission potential and possible pathogenesis in humans, aiming for a better understanding of bat SARS-related CoVs in the context of prevention and control.

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