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Parasites can manipulate the behavior of their hosts in ways that increase either their direct fitness or transmission to new hosts. The Kingdom Fungi have evolved a diverse array of strategies to manipulate arthropod behavior resulting in some of the most complex and impressive examples of behavioral manipulation by parasites. Here we provide an overview of these different interactions and discuss them from an evolutionary perspective. We discuss parasite manipulation within the context of Niko Tinbergen's four questions (function, phylogeny, causation, and ontogeny) before detailing the proximate mechanisms by which fungi control arthropod behavior and the evolutionary pathways to such adaptations. We focus on some systems for which we have recently acquired new knowledge (such as the zombie ant fungus, Ophiocordyceps unilateralis s.l.), but a major goal is also to highlight how many interesting examples remain to be discovered and investigated. With this in mind, we also discuss likely examples of manipulated spiders that are largely unexplored ("zombie spiders"). Armed with advanced tools in evolutionary biology (from serial block face SEM to RNAseq) we can discover how the fungi, a group of microbes capable of coordinated activity, have evolved the ability to direct animal behavior. In short, we have the ability to understand how the organism without the brain controls the one with the brain. We hope such a goal, coupled with the knowledge that many diverse examples of control exist, will inspire other organismal biologists to study the complex adaptations that have arisen from "so simple a beginning.", (Copyright © 2016 Elsevier Inc. All rights reserved.)

The entomopathogenic fungi are organisms that evolved to exploit insects. They comprise a wide range of morphologically, phylogenetically, and ecologically diverse fungal species. Entomopathogenic fungi can be found distributed among five of the eight fungal phyla. Entomopathogens are also present among the ecologically similar but phylogenetically distinct Oomycota or water molds, which belong to a different kingdom, the Stramenopila. As a group of parasites, the entomopathogenic fungi and water molds infect a wide range of insect hosts, from aquatic larvae to adult insects from high canopies in tropical forests or even deserts. Their hosts are spread among 20 of the 31 orders of insects, in all developmental stages: eggs, larvae, pupae, nymphs, and adults. Such assortment of niches has resulted in these parasites evolving a considerable morphological diversity, resulting in enormous biodiversity, the majority of which remains unknown. Here we undertake a comprehensive survey of records of these entomopathogens in order to compare and contrast both their morphologies and their ecological traits. Our findings highlight a wide range of adaptations that evolved following the evolutionary transition by the fungi and water molds to infect the most diverse and widespread animals on Earth, the insects., (Copyright © 2016 Elsevier Inc. All rights reserved.)

The increased incidence of fungal infections and the development of drug resistance have led to the search for microorganisms capable of producing bioactive metabolites with antifungal activity. Among these microorganisms, Streptomyces spp are distinguished mainly owing to their potential to secrete bioactive molecules. The aim of this study was to evaluate the production of secondary metabolites by Streptomyces sp TUR-10 against 12 fungal clinical isolates (yeast and filamentous fungi). In the preliminary screening, Streptomyces sp TUR-10 showed activity against 75% of the clinical isolates, and was selected for fermentation. In this assay, we tested three different media (MPE, M1, and ISP-4) for 96 h at pH 7.0 and 30°C for the production of bioactive metabolites. Increased production of bioactive compounds was observed when using the MPE medium for 48 h, with good activity against Candida pelliculosa. The minimum inhibitory concentration showed significant antifungal activity values ranging from 15.6 to 250 μg/mL. The actinobacterium was characterized by 16S rRNA analysis and the pattern suggested that the isolate studied belonged to the species Streptomyces ansochromogenes. The biotechnological potential of this strain was also demonstrated by the detection of the nrps and pks genes. These results indicate the production of secondary metabolites of biotechnological interest by actinobacteria from the rhizosphere, suggesting great potential for further research.

The predatory capacity of nematophagous fungi Duddingtonia flagrans (AC001), Monacrosporium thaumasium (NF34a), M. appendiculatum (CGI), M. sinense (SF53), Arthrobotrys conoides (I-40), A. cladodes (CG719) and A. robusta (I-31) on infective Ancylostoma sp. larvae (L3) was evaluated. Compared with the control without fungi there was a significant reduction (P < 0.05) of 87.02%, 82.74%, 47.93%, 60.49%, 76.89%, 71.33% and 86.02% in the mean number of Ancylostoma sp. (L3) recovered from treatments with the isolates AC001, NF34a, CGI, SF53, I-40, CG719 and I-31, respectively. Isolates AC001, I-31 and NF34a were more effective in capturing L3 during the in vitro assay. Isolates were then in vivo evaluated for the capacity to remain viable after passing through the gastrointestinal tract of dogs, while still maintaining their predatory activity against L3. Fungal isolates survived the passage and showed efficient predation 48 h after fungal administration to the dogs (P < 0.05). After this time, only the isolate NF34a remained effective up to 96 h after administration (P < 0.05). Monacrosporium thaumasium, D. flagrans and A. robusta are potential biological control agents of Ancylostoma sp. in dogs.

In the present work, it was evaluated the in vitro effect of 12 isolates from the fungal species Arthrobotrys, Duddingtonia, Nematoctonus and Monacrosporium genera in different conidial concentrations on the capture of Ancylostoma spp. dog infective larvae (L(3)), on 2% water-agar medium at 25 degrees C, at the end of a period of 7 days. The concentrations used for each nematophagous fungus were 1000, 5000, 10,000, 15,000 and 20,000conidia/Petri dish plated with 1000 Ancylostoma spp. L(3). All nematode-trapping fungi isolates tested reduced the averages of the uncaptured Ancylostoma spp. L(3) recovered, with the increase of the fungal inoculum concentration, in comparison to the fungus-free control (p<0.05). The adhesive network producing species were better predators than the constricting ring or adhesive knob producing species. Duddingtonia flagrans (Isolate CG768) was the most effective, reducing the averages of the uncaptured Ancylostoma spp. L(3) recovered in 92.8%, 96.3%, 97.5%, 98.3% and 98.9%, respectively in five fungal inoculum concentrations established. Other effective nematophagous fungi were Arthrobotrys robusta (Isolate I31), which reduced the averages of the uncaptured Ancylostoma spp. L(3) recovered in 85.4%, 88.3%, 90.7%, 92.5% and 95.2%, and Arthrobotrys oligospora (Isolate A183), with reductions of 66.6%, 79.8%, 86.8%, 89.5% and 90.8%, respectively for both, in the five fungal inoculum concentrations established. No difference was found between Isolates A183 and I31 in the conidial concentrations of 15,000/Petri dish. Nematoctonus robustus (Isolate D1) and Arthrobotrys bronchophaga (Isolate AB) had the smallest percentages of reduction among the tested isolates and showed the lowest predacious activity. The Isolates CG768, I31 and A183 were considered potential biological control agents of Ancylostoma spp. dog free-living stages, being directly influenced by the fungal inoculum concentration.

Extraction and isoenzyme analysis of four isolates of Arthrobotrys including A. musiformis, A. robusta and A. conoides were conducted. Among the 14 enzymes studied by starch gel electrophoresis, using morpholine-citrate as gel/electrode buffer, the following nine enzymes showed interpretable banding patterns: alpha-esterase, fumarase, hexokinase, isocitrate dehydrogenase, leucine aminopeptidase, malate dehydrogenase, 6-phosphogluconate dehydrogenase, phosphoglucomutase and phosphoglucoisomerase. All isolates studied displayed typical isoenzyme phenotypes for each species. Two isolates of A. conoides differed in their alpha-isoesterase banding patterns, but no differences were observed for the other enzymes. The assay was satisfactory for enzyme extraction and resolution of Arthrobotrys and could be used in future taxonomic and genetic studies of this organism.

During surveys in central Florida of the zombie-ant fungus Ophiocordyceps camponoti-floridani, which manipulates the behavior of the carpenter ant Camponotus floridanus, two distinct fungal morphotypes were discovered associated with and purportedly parasitic on O. camponoti-floridani. Based on a combination of unique morphology, ecology and phylogenetic placement, we discovered that these morphotypes comprise two novel lineages of fungi. Here, we propose two new genera, Niveomyces and Torrubiellomyces, each including a single species within the families Cordycipitaceae and Ophiocordycipitaceae, respectively. We generated de novo draft genomes for both new species and performed morphological and multi-loci phylogenetic analyses. The macromorphology and incidence of both new species, Niveomyces coronatus and Torrubiellomyces zombiae, suggest that these fungi are mycoparasites since their growth is observed exclusively on O. camponoti-floridani mycelium, stalks and ascomata, causing evident degradation of their fungal hosts. This work provides a starting point for more studies into fungal interactions between mycopathogens and entomopathogens, which have the potential to contribute towards efforts to battle the global rise of plant and animal mycoses. [ABSTRACT FROM AUTHOR]

Ophiocordyceps species infecting ants are globally distributed, with diversity concentrated in the tropics and decreasing with increasing latitude. Among these myrmecophilous species, the ones exhibiting the ability to manipulate host behavior, the so-called "zombie-ant fungi" of the O. unilateralis clade, have been studied progressively over the last decade. However, we know very little about other myrmecophilous groups, such as species within the Ophiocordyceps subgenus Neocordyceps. Species within this group exhibit Hymenostilbe asexual morphs with the ascospores readily breaking into part-spores and regularly kill their hosts on the forest floor, with few records of behavioral manipulation. Here, we describe five new species of Ophiocordyceps belonging to the subgenus Neocordyceps infecting ants in the rainforests of the Brazilian Amazon and Ghana and analyze their ability to manipulate host behavior. We also propose a new status for a species previously described as a variety, providing its phylogenetic placement for the first time. The species proposed herein can readily be separated using classic taxonomic criteria, and this is further supported by ecological and molecular multiloci data. [ABSTRACT FROM AUTHOR]

The action of four fungal isolates of the species Duddingtonia flagrans (AC001), Monacrosporium thaumasium (NF34a) and Pochonia chlamydosporia (VC1 and VC4) on eggs of Oxyuris equi and Austroxyuris finlaysoni was evaluated in two assays (A and B). Eggs of O. equi (Test A) and A. finlaysoni (Test B) were plated on Petri dishes with 2% water-agar with grown fungal isolates and control without fungus. After 5, 10 and 15 days, 100 eggs were collected and classified according to the following parameters: type 1 effect, physiological and biochemical effect without morphological damage to the eggshell; type 2 effect, lytic effect with morphological alteration of the eggshell and embryo; and type 3 effect, lytic effect with morphological alteration of the eggshell and embryo, hyphal penetration and internal egg colonization. Pochonia chlamydosporia isolates VC1 and VC4 showed ovicidal activity for type 1, 2 and 3 effects on eggs of O. equi and eggs of A. finlaysoni. In vitro assays A and B showed that P. chlamydosporia had a negative influence on eggs of O. equi and A. finlaysoni and can be considered as a potential biological control agent of nematodes. [ABSTRACT FROM AUTHOR]