Phylogenetic Diversity and Mycotoxin Potential of Emergent Phytopathogens within the Fusarium tricinctum Species Complex

Recent studies on multiple continents indicate members of the Fusarium tricinctum species complex (FTSC) are emerging as prevalent pathogens of small-grain cereals, pulses, and other economically important crops. These understudied fusaria produce structurally diverse mycotoxins, among which enniatins (ENNs) and moniliformin (MON) are the most frequent and of greatest concern to food and feed safety. Herein a large survey of fusaria in the Fusarium Research Center and Agricultural Research Service culture collections was undertaken to assess species diversity and mycotoxin potential within the FTSC. A 151-strain collection originating from diverse hosts and substrates from different agroclimatic regions throughout the world was selected from 460 FTSC strains to represent the breadth of FTSC phylogenetic diversity. Evolutionary relationships inferred from a 5-locus dataset, using maximum likelihood and parsimony, resolved the 151 strains as 24 phylogenetically distinct species, including nine that are new to science. Of the five genes analyzed, nearly full-length phosphate permease sequences contained the most phylogenetically informative characters, establishing its suitability for species-level phylogenetics within the FTSC. Fifteen of the species produced ENNs, MON, the sphingosine analog 2-amino-14,16- dimethyloctadecan-3-ol (AOD), and the toxic pigment aurofusarin (AUR) on a cracked corn kernel substrate. Interestingly, the five earliest diverging species in the FTSC phylogeny (i.e., F. iranicum, F. flocciferum, F. torulosum, Fusarium spp. FTSC 8 and 24) failed to produce AOD and MON, but synthesized ENNs and/or AUR. Moreover, our reassessment of nine published phylogenetic studies on the FTSC identified 11 additional novel taxa, suggesting this complex comprises at least 36 species.

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Phylogenetic diversity, trichothecene potential, and pathogenicity within Fusarium sambucinum species complex

PLoS ONE ◽

10.1371/journal.pone.0245037 ◽

2021 ◽

Vol 16 (1) ◽

pp. e0245037

Author(s):

Imane Laraba ◽

Susan P. McCormick ◽

Martha M. Vaughan ◽

David M. Geiser ◽

Kerry O’Donnell

Keyword(s):

Species Complex ◽

Plant Pathogens ◽

Novel Species ◽

Type A ◽

Distinct Species ◽

Fusarium Sambucinum ◽

In Planta ◽

Strain Collection ◽

Type A Trichothecenes

The Fusarium sambucinum species complex (FSAMSC) is one of the most taxonomically challenging groups of fusaria, comprising prominent mycotoxigenic plant pathogens and other species with various lifestyles. Among toxins produced by members of the FSAMSC, trichothecenes pose the most significant threat to public health. Herein a global collection of 171 strains, originating from diverse hosts or substrates, were selected to represent FSAMSC diversity. This strain collection was used to assess their species diversity, evaluate their potential to produce trichothecenes, and cause disease on wheat. Maximum likelihood and Bayesian analyses of a combined 3-gene dataset used to infer evolutionary relationships revealed that the 171 strains originally received as 48 species represent 74 genealogically exclusive phylogenetically distinct species distributed among six strongly supported clades: Brachygibbosum, Graminearum, Longipes, Novel, Sambucinum, and Sporotrichioides. Most of the strains produced trichothecenes in vitro but varied in type, indicating that the six clades correspond to type A, type B, or both types of trichothecene-producing lineages. Furthermore, five strains representing two putative novel species within the Sambucinum Clade produced two newly discovered type A trichothecenes, 15-keto NX-2 and 15-keto NX-3. Strains of the two putatively novel species together with members of the Graminearum Clade were aggressive toward wheat when tested for pathogenicity on heads of the susceptible cultivar Apogee. In planta, the Graminearum Clade strains produced nivalenol or deoxynivalenol and the aggressive Sambucinum Clade strains synthesized NX-3 and 15-keto NX-3. Other strains within the Brachygibbosum, Longipes, Novel, Sambucinum, and Sporotrichioides Clades were nonpathogenic or could infect the inoculated floret without spreading within the head. Moreover, most of these strains did not produce any toxin in the inoculated spikelets. These data highlight aggressiveness toward wheat appears to be influenced by the type of toxin produced and that it is not limited to members of the Graminearum Clade.

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Comparative genomics suggests a taxonomic revision of the Staphylococcus cohnii species complex

Genome Biology and Evolution ◽

10.1093/gbe/evab020 ◽

2021 ◽

Author(s):

Anna Lavecchia ◽

Matteo Chiara ◽

Caterina De Virgilio ◽

Caterina Manzari ◽

Carlo Pazzani ◽

...

Keyword(s):

Comparative Genomics ◽

Species Complex ◽

Large Scale ◽

Genomic Sequence ◽

Bacterial Species ◽

Taxonomic Revision ◽

Distinct Species ◽

The Novel ◽

Staphylococcus Cohnii ◽

Taxonomic Assignments

Abstract Staphylococcus cohnii (SC), a coagulase-negative bacterium, was first isolated in 1975 from human skin. Early phenotypic analyses led to the delineation of two subspecies (subsp.), Staphylococcus cohnii subsp. cohnii (SCC) and Staphylococcus cohnii subsp. urealyticus (SCU). SCC was considered to be specific to humans whereas SCU apparently demonstrated a wider host range, from lower primates to humans. The type strains ATCC 29974 and ATCC 49330 have been designated for SCC and SCU, respectively. Comparative analysis of 66 complete genome sequences—including a novel SC isolate—revealed unexpected patterns within the SC complex, both in terms of genomic sequence identity and gene content, highlighting the presence of 3 phylogenetically distinct groups. Based on our observations, and on the current guidelines for taxonomic classification for bacterial species, we propose a revision of the SC species complex. We suggest that SCC and SCU should be regarded as two distinct species: SC and SU (Staphylococcus urealyticus), and that two distinct subspecies, SCC and SCB (SC subsp. barensis, represented by the novel strain isolated in Bari) should be recognized within SC. Furthermore, since large scale comparative genomics studies recurrently suggest inconsistencies or conflicts in taxonomic assignments of bacterial species, we believe that the approach proposed here might be considered for more general application.

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Ten Years of Lateral Flow Immunoassay Technique Applications: Trends, Challenges and Future Perspectives

Sensors ◽

10.3390/s21155185 ◽

2021 ◽

Vol 21 (15) ◽

pp. 5185

Author(s):

Fabio Di Nardo ◽

Matteo Chiarello ◽

Simone Cavalera ◽

Claudio Baggiani ◽

Laura Anfossi

Keyword(s):

Environmental Control ◽

Improve Patient Care ◽

Turnaround Time ◽

Lateral Flow ◽

Lateral Flow Immunoassay ◽

Future Perspectives ◽

Immunoassay Technique ◽

Food And Feed ◽

Application Fields ◽

Feed Safety

The Lateral Flow Immunoassay (LFIA) is by far one of the most successful analytical platforms to perform the on-site detection of target substances. LFIA can be considered as a sort of lab-in-a-hand and, together with other point-of-need tests, has represented a paradigm shift from sample-to-lab to lab-to-sample aiming to improve decision making and turnaround time. The features of LFIAs made them a very attractive tool in clinical diagnostic where they can improve patient care by enabling more prompt diagnosis and treatment decisions. The rapidity, simplicity, relative cost-effectiveness, and the possibility to be used by nonskilled personnel contributed to the wide acceptance of LFIAs. As a consequence, from the detection of molecules, organisms, and (bio)markers for clinical purposes, the LFIA application has been rapidly extended to other fields, including food and feed safety, veterinary medicine, environmental control, and many others. This review aims to provide readers with a 10-years overview of applications, outlining the trends for the main application fields and the relative compounded annual growth rates. Moreover, future perspectives and challenges are discussed.

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Occurrence, Impact on Agriculture, Human Health, and Management Strategies of Zearalenone in Food and Feed: A Review

Toxins ◽

10.3390/toxins13020092 ◽

2021 ◽

Vol 13 (2) ◽

pp. 92

Author(s):

Dipendra Kumar Mahato ◽

Sheetal Devi ◽

Shikha Pandhi ◽

Bharti Sharma ◽

Kamlesh Kumar Maurya ◽

...

Keyword(s):

Human Health ◽

Control Strategies ◽

Management Strategies ◽

Structural Similarity ◽

Fungal Metabolites ◽

Natural Estrogens ◽

Food And Feed ◽

Feed Safety ◽

And Control ◽

Different Sources

Mycotoxins represent an assorted range of secondary fungal metabolites that extensively occur in numerous food and feed ingredients at any stage during pre- and post-harvest conditions. Zearalenone (ZEN), a mycotoxin categorized as a xenoestrogen poses structural similarity with natural estrogens that enables its binding to the estrogen receptors leading to hormonal misbalance and numerous reproductive diseases. ZEN is mainly found in crops belonging to temperate regions, primarily in maize and other cereal crops that form an important part of various food and feed. Because of the significant adverse effects of ZEN on both human and animal, there is an alarming need for effective detection, mitigation, and management strategies to assure food and feed safety and security. The present review tends to provide an updated overview of the different sources, occurrence and biosynthetic mechanisms of ZEN in various food and feed. It also provides insight to its harmful effects on human health and agriculture along with its effective detection, management, and control strategies.

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Food and feed safety: Cases and approaches to identify the responsible toxins and toxicants

Food Control ◽

10.1016/j.foodcont.2018.10.028 ◽

2019 ◽

Vol 98 ◽

pp. 9-18 ◽

Cited By ~ 1

Author(s):

Arjen Gerssen ◽

Toine H.F. Bovee ◽

Leendert A. van Ginkel ◽

Marlou L.P.S. van Iersel ◽

Ron L.A.P. Hoogenboom

Keyword(s):

Food And Feed ◽

Safety Cases ◽

Feed Safety ◽

Food And Feed Safety

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Influences of oceanic islands and the Pleistocene on the biogeography and evolution of two groups of Australasian parrots (Aves: Psittaciformes: Eclectus roratus, Trichoglossus haematodus complex). Rapid evolution and implications for taxonomy and conservation

European Journal of Ecology ◽

10.1515/eje-2017-0014 ◽

2016 ◽

Vol 3 (2) ◽

pp. 47-66

Author(s):

Michael P. Braun ◽

Matthias Reinschmidt ◽

Thomas Datzmann ◽

David Waugh ◽

Rafael Zamora ◽

...

Keyword(s):

Species Complex ◽

Rapid Evolution ◽

New Guinea ◽

Distinct Species ◽

Genetic Evidence ◽

Valid Species ◽

Separate Species ◽

Species Complexes ◽

Mitochondrial Cytochrome B ◽

Avian Diversification

AbstractThe Australasian region is a centre of biodiversity and endemism, mainly based on the tropical climate in combination with the large amount of islands. During the Pleistocene, islands of the Sahul Shelf (Australia, New Guinea, Aru Islands) had been part of the same land mass, while islands within the Wallacea (Lesser Sunda Islands, Moluccas, Sulawesi etc.) remained isolated. We investigated biogeographical avian diversification patterns of two species complexes across the Wallacea and the Sahul Shelf: the Eclectus Parrot Eclectus roratus Wagler, 1832, and the Rainbow Lorikeet Trichoglossus haematodus Linnaeus, 1771. Both species are represented by a large number of described geographical subspecies. We used mitochondrial cytochrome b (cyt b) sequences for phylogenetic and network analysis to detect biogeographic roles of islands and avian diversification patterns. The number of threatened taxa in this region is increasing rapidly and there is an urgent need for (sub-)species conservation in this region. Our study provides first genetic evidence for treating several island taxa as distinct species. In both species complexes similar genetic patterns were detected. Genetic diversification was higher across the islands of the Wallacea than across the islands of the Sahul Shelf. Divergence in E. roratus can be dated back about 1.38 million years ago, whereas in the younger T. haematodus it was 0.80 million years ago. Long distance dispersal was the most likely event for distribution patterns across the Wallacea and Sahul Shelf. The geographic origin of the species-complex Eclectus roratus spp. is supposed to be Wallacean, but for the species-complex Trichoglossus haematodus spp. it is supposed to be non-Wallacean. Trichoglossus euteles, so far considered a distinct species, clearly belongs to the Trichoglossus-haematodus-complex. The only case of sympatry in the complex is the distribution of T. (h.) euteles and T. h. capistratus on Timor, which means a rapid evolution from one ancestor into two distinct species within only 800,000 years. For all other taxa a Checkerboard distribution pattern is present. In this complex, 8 taxa are already treated as separate species (del Hoyo et al. 2014). Based on genetic evidence, the following populations are supported to represent phylogenetic units: (1) N New Guinea (haematodus) incl. Biak (rosenbergii), Bismarck Archipelago (massena), and New Caledonia (deplanchii); (2) Flores (weberi); (3) E Australia (moluccanus) incl. Aru Islands (nigrogularis) and S New Guinea (caeruleiceps); (4) N Australia (rubritorquis); (5) Timor 1st lineage (capistratus) incl. Sumba (fortis); (6) Bali and Lombok (mitchellii); (7) Sumbawa (forsteni); (8) Timor 2nd lineage (euteles). Those 8 phylogenetic units are not identical to the 8 species listed by del Hoyo et al. (2014). Several populations on smaller islands are under decline, a separate species status may lead to a higher conservation status in both species complexes, which are currently listed as “Least Concern”. Eclectus roratus is currently treated as monospecific. Based on genetic evidence, the following populations are suggested being treated as valid species: (1) Sumba (Eclectus cornelia), (2) Tanimbar Islands (E. riedeli), (3) Moluccas (E. roratus), and (4) New Guinea (E. polychloros incl. Aru Islands (E. aruensis), and Solomon Island (E. solomonensis).

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Reference on Mycotoxins Occurrence, Prevalence, and Risk Assessment in Food Systems

Novel Technologies and Systems for Food Preservation - Practice, Progress, and Proficiency in Sustainability ◽

10.4018/978-1-5225-7894-9.ch012 ◽

2019 ◽

pp. 294-343

Author(s):

Griffiths Atungulu ◽

Zeinab Mohammadi-Shad

Keyword(s):

Risk Assessment ◽

Filamentous Fungi ◽

Human Exposure ◽

Food Systems ◽

Economic Losses ◽

Animal Products ◽

Food And Feed ◽

Feed Safety ◽

And Storage ◽

Food And Feed Safety

Mycotoxins are a group of naturally occurring toxins that are produced by different filamentous fungi genera such as Aspergillus, Penicillium, Fusarium, etc. The word mycotoxin literally is derived from Greek word “myke” meaning fungus and “toxicum” meaning toxin. These contaminants can develop on different food and feed commodities during different stages including pre-harvest, harvest, and storage. Mycotoxins are of concern because their outbreak result in animal and human diseases and economic losses. It has been estimated that global post-harvest losses are approximately at 50%. Human exposure to mycotoxins is typically through consumption of contaminated agricultural products or indirectly by consumption of animal products containing mycotoxins or their metabolites. The chapter provides the latest information on mycotoxin issues and challenges related to food and feed safety.

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An In Silico Target Fishing Approach to Identify Novel Ochratoxin A Hydrolyzing Enzyme

Toxins ◽

10.3390/toxins12040258 ◽

2020 ◽

Vol 12 (4) ◽

pp. 258 ◽

Cited By ~ 1

Author(s):

Luca Dellafiora ◽

Christoph Gonaus ◽

Barbara Streit ◽

Gianni Galaverna ◽

Wulf-Dieter Moll ◽

...

Keyword(s):

Ochratoxin A ◽

In Silico ◽

Fungal Species ◽

Mitigation Strategies ◽

Carboxypeptidase B ◽

Enzymatic Assays ◽

Food And Feed ◽

Hydrolyzing Enzymes ◽

Feed Safety

Ochratoxin A (OTA), a mycotoxin that is of utmost concern in food and feed safety, is produced by fungal species that mainly belong to the Aspergillus and Penicillium genera. The development of mitigation strategies to reduce OTA content along the supply chains is key to ensuring safer production of food and feed. Enzyme-based strategies are among the most promising methods due to their specificity, efficacy, and multi-situ applicability. In particular, some enzymes are already known for hydrolyzing OTA into ochratoxin alpha (OTα) and phenylalanine (Phe), eventually resulting in detoxification action. Therefore, the discovery of novel OTA hydrolyzing enzymes, along with the advancement of an innovative approach for their identification, could provide a broader basis to develop more effective mitigating strategies in the future. In the present study, a hybrid in silico/in vitro workflow coupling virtual screening with enzymatic assays was applied in order to identify novel OTA hydrolyzing enzymes. Among the various hits, porcine carboxypeptidase B was identified for the first time as an effective OTA hydrolyzing enzyme. The successful experimental endorsement of findings of the workflow confirms that the presented strategy is suitable for identifying novel OTA hydrolyzing enzymes, and it might be relevant for the discovery of other mycotoxin- mitigating enzymes.

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