scholarly journals The host range of Aphis gossypii is dependent on aphid genetic background and feeding experience

PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e7774 ◽  
Author(s):  
Lin Ma ◽  
Meng-Yue Li ◽  
Chun-Yan Chang ◽  
Fang-Fang Chen ◽  
Yang Hu ◽  
...  
Keyword(s):  
Secondary Metabolites ◽  
Host Range ◽  
Host Plants ◽  
Artificial Diet ◽  
Aphis Gossypii ◽  
Host Specialization ◽  
Broad Host Range ◽  
Feeding Experience ◽  
Wide Range ◽  
Cotton Plants

Background A polyphagous insect herbivore has a wide range of host plants. However, it has been found that many polyphagous herbivores commonly exhibit a strong preference for a subset of species in their broad host range, and various host biotypes exist in herbivore populations. Nutrition and secondary metabolites in plants affect herbivore preference and performance, but it is still not clear which factors determine the host range and host preference of polyphagous herbivores. Method Cotton-melon aphids, Aphis gossypii Glover, collected from cotton and cucumber crops, were used in this study. The genetic backgrounds of these aphids were detected using microsatellite PCR and six genotypes were evaluated. Performance of these six aphid genotypes on excised leaves and plants of cotton and cucumber seedlings were examined through a reciprocal transplant experiment. In order to detect whether the feeding experience on artificial diet would alter aphid host range, the six genotypes of aphids fed on artificial diet for seven days were transferred onto cotton and cucumber leaves, and then their population growth on these two host plants was surveyed. Results Aphids from cotton and cucumber plants could not colonize the excised leaves and intact plants of cucumber and cotton seedlings, respectively. All six genotypes of aphids collected from cotton and cucumber plants could survive and produce offspring on artificial diet, which lacked plant secondary metabolites. The feeding experience on the artificial diet did not alter the ability of all six genotypes to use their native host plants. However, after feeding on this artificial diet for seven days, two aphid genotypes from cotton and one from cucumber acquired the ability to use both of the excised leaves from cucumber and cotton plants. The two aphid genotypes from cotton conditioned by the feeding experience on artificial diet and then reared on excised cucumber leaves for >12 generations still maintained the ability to use intact cotton plants but did not establish a population on cucumber plants. However, one cucumber genotype conditioned by artificial diet and then reared on excised cotton leaves could use both the intact cotton and cucumber plants, showing that the expansion of host range was mediated by feeding experience. Conclusion Feeding experience on artificial diet induced the expansion of host range of the cucurbit-specialized A. gossypii, and this expansion was genotype-specific. We speculated that feeding on a constant set of host plants in the life cycle of aphids may contribute to the formation of host specialization.

scholarly journals Revealing biophysical properties of KfrA-type proteins as a novel class of cytoskeletal, coiled-coil plasmid-encoded proteins

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
M. Adamczyk ◽  
E. Lewicka ◽  
R. Szatkowska ◽  
H. Nieznanska ◽  
J. Ludwiczak ◽  
...  
Keyword(s):  
Dna Binding ◽  
Host Range ◽  
Coiled Coil ◽  
Amino Acid Sequences ◽  
Broad Host Range ◽  
Biophysical Properties ◽  
Dna Binding Sites ◽  
In Silico Studies ◽  
Wide Range

Abstract Background DNA binding KfrA-type proteins of broad-host-range bacterial plasmids belonging to IncP-1 and IncU incompatibility groups are characterized by globular N-terminal head domains and long alpha-helical coiled-coil tails. They have been shown to act as transcriptional auto-regulators. Results This study was focused on two members of the growing family of KfrA-type proteins encoded by the broad-host-range plasmids, R751 of IncP-1β and RA3 of IncU groups. Comparative in vitro and in silico studies on KfrAR751 and KfrARA3 confirmed their similar biophysical properties despite low conservation of the amino acid sequences. They form a wide range of oligomeric forms in vitro and, in the presence of their cognate DNA binding sites, they polymerize into the higher order filaments visualized as “threads” by negative staining electron microscopy. The studies revealed also temperature-dependent changes in the coiled-coil segment of KfrA proteins that is involved in the stabilization of dimers required for DNA interactions. Conclusion KfrAR751 and KfrARA3 are structural homologues. We postulate that KfrA type proteins have moonlighting activity. They not only act as transcriptional auto-regulators but form cytoskeletal structures, which might facilitate plasmid DNA delivery and positioning in the cells before cell division, involving thermal energy.

scholarly journals A65 Characterization of endolysin gene of bacteriophages infecting Listeria spp. isolated from dairy industry wastewater

2019 ◽  
Vol 5 (Supplement_1) ◽  
Author(s):  
Blanco Fernández ◽  
M E Barrios ◽  
R V Cammarata ◽  
C Torres ◽  
V A Mbayed
Keyword(s):  
Host Range ◽  
High Titer ◽  
Dairy Industry ◽  
Foodborne Pathogen ◽  
Dairy Farm ◽  
Restriction Enzymes ◽  
Invasive Disease ◽  
Broad Host Range ◽  
Wide Range ◽  
Industry Wastewater

Abstract Bacteriophages and their endolysins, enzymes that degrade the cell walls of bacteria, are emerging as alternative tools to detect and inhibit growth of pathogen bacteria. Listeria monocytogenes is a foodborne pathogen that causes listeriosis, a serious invasive disease that affects both humans and a wide range of animals. Listeria spp. are ubiquitous in the dairy farm environment and could be present in dairy-processing plants and wastewater. All Listeria-specific bacteriophages found to date are members of the Caudovirales, of the Siphoviridae or Myoviridae families. Myophages infecting Listeria have been recently classified by the ICTV in the Spounavirinae subfamily, as well as in the P100 virus genus. The aim of this work was to isolate Listeria spp. bacteriophages and their endolysin codifying genes from wastewater of a dairy industry. Wastewater with and without treatment was sampled during the course of a year, and isolation of bacteriophages was performed after an enrichment step using as hosts L. innocua, L. ivanovii, and L. monocytogenes serotypes 1/2a, 1/2b, and 4b. Bacteriophages infecting L. innocua and L. ivanovii were isolated (n = 24) from 3 out of 12 samples. Bacteriophages were purified, and the host range was determined using spot test and EOP against five collection strains and several field isolates of Listeria spp. Two bacteriophages of narrow and broad host range, vB_Lino_VEfB7, and vB_Liva_VAfA18, were selected for further characterization. High titer stocks of bacteriophages were purified by centrifugation with ammonium acetate, and morphological information on the purified bacteriophages was obtained by negative staining and transmission electronic microscopy. Their morphology, size, and contractile tails indicated that these bacteriophages belonged to the Myoviridae family. Bacteriophage genomes were extracted using phenol-chloroform, followed by ethanol precipitation, and tested by digestion with RNAsa A and DNAse I. RFLP was performed, digesting genomes with restriction enzymes HindIII and NcoI. Consistent with the morphological findings, bacteriophages contained dsDNA genomes but showed different RFLP patterns. A PCR designed to amplify conserved domains of endolysins—PGRP and CwlA—was applied to characterize this gene. Another PCR was designed to amplify the complete endolysin gene, and the complete sequence of this gene was obtained and analyzed. Substitution model selection and a maximum likelihood phylogenetic tree of the endolysin gene was carried out using IQ-Tree software. The sequences of the endolysin gene indicated that the codified enzyme is an N-acetyl-muramoyl-L-alanine amidase, related to A511 and P100 species of the recently described P100virus genus. Further evolutionary analyses are needed to evaluate their belonging to this species or their taxonomy within this genus.

Limits to the host range of the highly polyphagous tephritid fruit fly Anastrepha ludens in its natural habitat

2015 ◽  
Vol 105 (6) ◽  
pp. 743-753 ◽  
Author(s):  
A. Birke ◽  
E. Acosta ◽  
M. Aluja
Keyword(s):  
Host Range ◽  
Natural Habitat ◽  
Fruit Fly ◽  
Natural Host ◽  
Pupal Weight ◽  
Anastrepha Ludens ◽  
Broad Host Range ◽  
Ripe Fruit ◽  
Natural Conditions ◽  
Wide Range

AbstractAnastepha ludens (Diptera: Tephritidae) is a highly polyphagous fruit fly that is able to develop in a wide range of hosts. Understanding the limits of this pest's host range could provide valuable information for pest management and plant breeding for pest resistance. Previous studies have shown that guavas (Psidium guajava (Myrtaceae) L.), are not attacked under natural conditions by A. ludens. To understand this phenomenon, guavas were exposed to natural infestation by A. ludens and to other fruit fly species that infest guavas in nature (Anastrepha striata Schiner, Anastepha fraterculus (Wiedemann), Anastepha obliqua (Macquart)). Once the susceptible phenological stage of guavas was determined, fruit infestation levels were compared between A. ludens and A. striata. Choice and non-choice tests were performed under field-cage conditions. Under field conditions, guavas were susceptible to A. striata and A. fraterculus attack all the way from when fruit was undeveloped to when fruit began to ripen. No infestation by A. ludens was recorded under natural conditions. Similar results were obtained when forced exposures were performed, indicating that unripe guavas were preferred by A. striata over ripe fruit, and that infestation rates were higher at early fruit maturity stages. Under forced oviposition conditions, A. ludens larvae were unable to develop in unripe guavas but did so in fully ripe fruit. However, A. ludens fitness parameters were dramatically affected, exhibiting reduced survival and reduced pupal weight compared to conspecifics that developed in a natural host, grapefruit. We confirm that P. guajava should not be treated as a natural host of this pestiferous species, and suggest that both behavioral aspects and the fact that larvae are unable to adequately develop in this fruit, indeed represent clear limits to A. ludens's broad host range.

scholarly journals A detailed in silico analysis of secondary metabolite biosynthesis clusters in the genome of the broad host range plant pathogenic fungus Sclerotinia sclerotiorum

2019 ◽  
Author(s):  
Carolyn Graham-Taylor ◽  
Lars G Kamphuis ◽  
Mark Derbyshire
Keyword(s):  
Secondary Metabolites ◽  
Host Range ◽  
Secondary Metabolite ◽  
Sclerotinia Sclerotiorum ◽  
Plant Pathogens ◽  
Pathogenic Fungus ◽  
Gene Clusters ◽  
Sequence Diversity ◽  
Broad Host Range ◽  
Data Set

Abstract Background The broad host range pathogen Sclerotinia sclerotiorum infects over 400 plant species and causes substantial yield losses in crops worldwide. Secondary metabolites are known to play important roles in the virulence of plant pathogens, but little is known about the secondary metabolite repertoire of S. sclerotiorum. In this study, we predicted secondary metabolite biosynthetic gene clusters in the genome of S. sclerotiorum and analysed their expression during infection of Brassica napus using an existing transcriptome data set. We also investigated their sequence diversity among a panel of 25 previously published S. sclerotiorum isolate genomes.Results We identified 80 putative secondary metabolite clusters. Over half of the clusters contained at least three transcriptionally coregulated genes. Comparative genomics revealed clusters homologous to clusters in the closely related plant pathogen Botrytis cinerea for production of carotenoids, hydroxamate siderophores, DHN melanin and botcinic acid. We also identified putative phytotoxin clusters that can potentially produce the polyketide sclerin and an epipolythiodioxopiperazine. Secondary metabolite clusters were enriched in subtelomeric genomic regions, and those containing paralogues showed a particularly strong association with repeats. The positional bias we identified was borne out by intraspecific comparisons that revealed putative secondary metabolite genes suffered more presence / absence polymorphisms and exhibited a significantly higher sequence diversity than other genes.Conclusions These data suggest that S. sclerotiorum produces numerous secondary metabolites during plant infection and that their gene clusters undergo enhanced rates of mutation, duplication and recombination in subtelomeric regions. The microevolutionary regimes leading to S. sclerotiorum secondary metabolite diversity have yet to be elucidated. Several potential phytotoxins documented in this study provide the basis for future functional analyses.

SOME HOST PLANTS OF A CANADIAN ISOLATE OF THE CLOVER PHYLLODY VIRUS

1967 ◽  
Vol 47 (2) ◽  
pp. 141-148 ◽  
Author(s):  
L. N. Chiykowski
Keyword(s):  
Host Range ◽  
Plant Species ◽  
Host Plants ◽  
Canadian Isolate ◽  
Wide Range ◽  
Clover Phyllody

Clover phyllody symptoms appeared on 34 species of plants in 13 families inoculated by infective Macrosteles fascifrons (Stål) or Aphrodes bicinctus (Schrank). Forty-five other species of plants in 12 families showed no infection although they were inoculated by insects shown to be infective by subsequent transmission to aster. M. fascifrons also transmitted CPV from 17 of 18 infected species tested. Characteristic symptoms on infected plants of some of the species are described and illustrated.Efficiency of transmission and the ability to survive on a wide range of plant species demonstrates the importance of M. fascifrons as a vector for host range studies.

scholarly journals Characterization of a broad-host-range flagellum-dependent phage that mediates high-efficiency generalized transduction in, and between, Serratia and Pantoea

Microbiology ◽  
2010 ◽  
Vol 156 (1) ◽  
pp. 240-247 ◽  
Author(s):  
T. J. Evans ◽  
M. A. Crow ◽  
N. R. Williamson ◽  
W. Orme ◽  
N. R. Thomson ◽  
...  
Keyword(s):  
Antibiotic Resistance ◽  
Cancer Therapy ◽  
Secondary Metabolites ◽  
Host Range ◽  
High Efficiency ◽  
Fungal Infections ◽  
Broad Host Range ◽  
Potential Applications ◽  
Generalized Transduction

A phage (ΦOT8) isolated on Serratia sp. ATCC 39006 was shown to be flagellum-dependent, and to mediate generalized transduction with high efficiency (up to 10−4 transductants per p.f.u.). ΦOT8 was shown to have a broad host range because it also infected a strain of Pantoea agglomerans isolated from the rhizosphere. Transduction of plasmid-borne antibiotic resistance between the two bacterial genera was demonstrated, consistent with purported ecological roles of phages in dissemination of genes between bacterial genera. Serratia sp. ATCC 39006 and P. agglomerans produce a number of interesting secondary metabolites that have potential applications in cancer therapy and biocontrol of fungal infections. ΦOT8 has utility as a powerful functional genomics tool in these bacteria.

An Experimental Test of the Host-Plant Range of Nonrecombinant Strains of North American Xylella fastidiosa subsp. multiplex

2019 ◽  
Vol 109 (2) ◽  
pp. 294-300 ◽  
Author(s):  
Leonard Nunney ◽  
Hamid Azad ◽  
Richard Stouthamer
Keyword(s):  
Homologous Recombination ◽  
Host Range ◽  
Xylella Fastidiosa ◽  
Sequence Type ◽  
Host Specialization ◽  
Washington Dc ◽  
Plant Host ◽  
Wide Range ◽  
Novel Host ◽  
Different Strains

Nonrecombinant strains of Xylella fastidiosa subsp. multiplex (those lacking evidence of significant intersubspecific homologous recombination) infect the xylem of a wide range of native and nonnative trees in North America. However, the degree to which different strains have a specialized host range remains poorly understood. We tested eight strains isolated from five different tree species (almond, olive, sweetgum, and plum in California and oak in Washington, DC). Experiments were conducted in greenhouses in Riverside, CA, and each strain was tested on 11 to 15 of the 17 plant species tested. Hosts infected by the most strains were plum (5 of 8 strains) and almond (4 of 8), while their congener peach was only infected by 1 of 8. No strains infected oleander or mulberry. All strains successfully infected their original host, with peach, olive (1 of 7), and sweetgum (2 of 6) only infected by such strains. Of the 90 total strain–novel-host combinations tested, 11 resulted in unambiguous infection, 2 gave ambiguous results, and the remaining 77 failed to result in symptoms or bacterial spread. All eight strains had a unique host range, including two pairs of strains with the same multilocus sequence typing sequence type, providing strong evidence of extensive plant-host specialization. There was little evidence that host relatedness was driving host specificity.

Plasticity in host utilization by two host-associated populations of Aphis gossypii Glover

2017 ◽  
Vol 108 (3) ◽  
pp. 360-369 ◽  
Author(s):  
A.K. Barman ◽  
K.R. Gadhave ◽  
B. Dutta ◽  
R. Srinivasan
Keyword(s):  
Host Plant ◽  
Plant Species ◽  
Host Plants ◽  
Aphis Gossypii ◽  
Agricultural Landscapes ◽  
Host Specialization ◽  
Intrinsic Rate Of Increase ◽  
Fitness Parameters ◽  
Aphid Populations ◽  
Host Utilization

AbstractBiological and morphological plasticity in polyphagous insect herbivores allow them to exploit diverse host plant species. Geographical differences in resource availability can lead to preferential host exploitation and result in inconsistent host specialization. Biological and molecular data provide insights into specialization and plasticity of such herbivore populations. In agricultural landscapes, Aphis gossypii encounters several crop and non-crop hosts, which exist in temporal and spatial proximity. We investigated the host-specialization of two A. gossypii host-associated populations (HAPs), which were field collected from cotton and squash (cotton-associated population and melon-associated population), and later maintained separately in the greenhouse. The two aphid populations were exposed to seven plant species (cotton, okra, watermelon, squash, cucumber, pigweed, and morning glory), and evaluated for their host utilization plasticity by estimating aphid's fitness parameters (nymphal period, adult period, fecundity, and intrinsic rate of increase). Four phenotypical characters (body length, head capsule width, hind tibia length and cornicle length) were also measured from the resulting 14 different HAP × host plant combinations. Phylogenetic analysis of mitochondrial COI sequences showed no genetic variation between the two HAPs. Fitness parameters indicated a significant variation between the two aphid populations, and the variation was influenced by host plants. The performance of melon-aphids was poor (up to 89% reduction in fecundity) on malvaceous hosts, cotton and okra. However, cotton-aphids performed better on cucurbitaceous hosts, squash and watermelon (up to 66% increased fecundity) compared with the natal host, cotton. Both HAPs were able to reproduce on two weed hosts. Cotton-aphids were smaller than melon-aphids irrespective of their host plants. Results from this study suggest that the two HAPs in the study area do not have strict host specialization; rather they exhibit plasticity in utilizing several hosts. In this scenario, it is unlikely that host-associated A. gossypii populations would evolve into host-specific biotypes.

scholarly journals Differential Binding of Host Complement Inhibitor Factor H by Borrelia burgdorferi Erp Surface Proteins: a Possible Mechanism Underlying the Expansive Host Range of Lyme Disease Spirochetes

2002 ◽  
Vol 70 (2) ◽  
pp. 491-497 ◽  
Author(s):  
Brian Stevenson ◽  
Nazira El-Hage ◽  
Melissa A. Hines ◽  
Jennifer C. Miller ◽  
Kelly Babb
Keyword(s):  
Lyme Disease ◽  
Borrelia Burgdorferi ◽  
Host Range ◽  
General Characteristic ◽  
Factor H ◽  
Surface Proteins ◽  
Broad Host Range ◽  
Complement Inhibitor ◽  
Wide Range ◽  
Mammalian Infection

ABSTRACT The Lyme disease spirochete, Borrelia burgdorferi, is capable of infecting a wide variety of vertebrates. This broad host range implies that B. burgdorferi possesses the ability to contravene the immune defenses of many potential hosts. B. burgdorferi produces multiple different Erp proteins on its outer membrane during mammalian infection. It was reported previously that one Erp protein can bind human factor H (J. Hellwage, T. Meri, T. Heikkilä, A. Alitalo, J. Panelius, P. Lahdenne, I. J. T. Seppälä, and S. Meri, J. Biol. Chem. 276:8427–8435, 2001). In this paper we report that the ability to bind the complement inhibitor factor H is a general characteristic of Erp proteins. Furthermore, each Erp protein exhibits different relative affinities for the complement inhibitors of various potential animal hosts. The data suggest that the presence of multiple Erp proteins on the surface can allow a single B. burgdorferi bacterium to resist complement-mediated killing in any of the wide range of potential hosts that it might infect. Thus, Erp proteins likely contribute to the persistence of B. burgdorferi in nature and to the ability of this bacterium to cause Lyme disease in humans and other animals.

scholarly journals A detailed in silico analysis of secondary metabolite biosynthesis clusters in the genome of the broad host range plant pathogenic fungus Sclerotinia sclerotiorum

BMC Genomics ◽  
2020 ◽  
Vol 21 (1) ◽  
Author(s):  
Carolyn Graham-Taylor ◽  
Lars G. Kamphuis ◽  
Mark C. Derbyshire
Keyword(s):  
Secondary Metabolites ◽  
Host Range ◽  
Secondary Metabolite ◽  
Sclerotinia Sclerotiorum ◽  
Plant Pathogens ◽  
Pathogenic Fungus ◽  
Gene Clusters ◽  
Sequence Diversity ◽  
Broad Host Range ◽  
Data Set

Abstract Background The broad host range pathogen Sclerotinia sclerotiorum infects over 400 plant species and causes substantial yield losses in crops worldwide. Secondary metabolites are known to play important roles in the virulence of plant pathogens, but little is known about the secondary metabolite repertoire of S. sclerotiorum. In this study, we predicted secondary metabolite biosynthetic gene clusters in the genome of S. sclerotiorum and analysed their expression during infection of Brassica napus using an existing transcriptome data set. We also investigated their sequence diversity among a panel of 25 previously published S. sclerotiorum isolate genomes. Results We identified 80 putative secondary metabolite clusters. Over half of the clusters contained at least three transcriptionally coregulated genes. Comparative genomics revealed clusters homologous to clusters in the closely related plant pathogen Botrytis cinerea for production of carotenoids, hydroxamate siderophores, DHN melanin and botcinic acid. We also identified putative phytotoxin clusters that can potentially produce the polyketide sclerin and an epipolythiodioxopiperazine. Secondary metabolite clusters were enriched in subtelomeric genomic regions, and those containing paralogues showed a particularly strong association with repeats. The positional bias we identified was borne out by intraspecific comparisons that revealed putative secondary metabolite genes suffered more presence / absence polymorphisms and exhibited a significantly higher sequence diversity than other genes. Conclusions These data suggest that S. sclerotiorum produces numerous secondary metabolites during plant infection and that their gene clusters undergo enhanced rates of mutation, duplication and recombination in subtelomeric regions. The microevolutionary regimes leading to S. sclerotiorum secondary metabolite diversity have yet to be elucidated. Several potential phytotoxins documented in this study provide the basis for future functional analyses.

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