scholarly journals Novel Viruses That Lyse Plant and Human Strains of Kosakonia cowanii

Viruses ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1418
Author(s):  
Karel Petrzik ◽  
Sára Brázdová ◽  
Krzysztof Krawczyk
Keyword(s):  
Host Specificity ◽  
Opportunistic Pathogen ◽  
New Genera ◽  
Pathogen Control ◽  
Plaque Phenotype

Kosakonia cowanii (syn. Enterobacter cowanii) is a highly competitive bacterium that lives with plant, insect, fish, bird, and human organisms. It is pathogenic on some plants and an opportunistic pathogen of human. Nine novel viruses that lyse plant pathogenic strains and/or human strains of K. cowanii were isolated, sequenced, and characterized. Kc166A is a novel kayfunavirus, Kc261 is a novel bonnellvirus, and Kc318 is a new cronosvirus (all Autographiviridae). Kc237 is a new sortsnevirus, but Kc166B and Kc283 are members of new genera within Podoviridae. Kc304 is a new winklervirus, and Kc263 and Kc305 are new myoviruses. The viruses differ in host specificity, plaque phenotype, and lysis kinetics. Some of them should be suitable also as pathogen control agents.

scholarly journals Analysis of large new South African dataset using two host-specificity indices shows generalism in both adult and larval ticks of mammals

Parasitology ◽  
2015 ◽  
Vol 143 (3) ◽  
pp. 366-373 ◽  
Author(s):  
MARCELA P. A. ESPINAZE ◽  
ELÉONORE HELLARD ◽  
IVAN G. HORAK ◽  
GRAEME S. CUMMING
Keyword(s):  
Host Specificity ◽  
South African ◽  
New South ◽  
Life Stage ◽  
Host Preferences ◽  
Infestation Intensity ◽  
Host Parasite Interactions ◽  
Host Phylogeny ◽  
Pathogen Control ◽  
Host Parasite

SUMMARYTicks and tick-borne pathogens can have considerable impacts on the health of livestock, wildlife and people. Knowledge of tick–host preferences is necessary for both tick and pathogen control. Ticks were historically considered as specialist parasites, but the range of sampled host species has been limited, infestation intensity has not been included in prior analyses, and phylogenetic distances between hosts have not been previously considered. We used a large dataset of 35 604 individual collections and two host-specificity indices to assess the specificity of 61 South African tick species, as well as distinctions between adult and juvenile ticks, for 95 mammalian hosts. When accounting for host phylogeny, most adult and juvenile ticks behaved as generalists, with juveniles being significantly more generalist than adults. When we included the intensity of tick infestation, ticks exhibited a wider diversity of specificity in all life stages. Our results show that ticks of mammals in South Africa tend to behave largely as generalists and that adult ticks are more host-specific. More generally, our analysis shows that the incorporation of life-stage differences, infestation intensity and phylogenetic distances between hosts, as well as the use of more than one specificity index, can all contribute to a deeper understanding of host–parasite interactions.

scholarly journals Early diverging insect pathogenic fungi of the order Entomophthorales possess diverse and unique subtilisin-like serine proteases

2018 ◽  
Author(s):  
Jonathan A. Arnesen ◽  
Joanna Malagocka ◽  
Andrii Gryganskyi ◽  
Igor V. Grigoriev ◽  
Kerstin Voigt ◽  
...  
Keyword(s):  
Host Specificity ◽  
Serine Proteases ◽  
Pathogenic Fungi ◽  
Opportunistic Pathogen ◽  
Protein Domain ◽  
Broad Host Range ◽  
Generalist Species ◽  
Formica Polyctena ◽  
Insect Pathogenic Fungi ◽  
Insect Pathogens

AbstractInsect-pathogenic fungi use subtilisin-like serine proteases (SLSPs) to degrade chitin-associated proteins in the insect procuticle. Most insect-pathogenic fungi in the order Hypocreales (Ascomycota) are generalist species with a broad host-range, and most species possess a high number of SLSPs. The other major clade of insect-pathogenic fungi is part of the subphylum Entomophthoromycotina (Zoopagomycota, formerly Zygomycota) which consists of high host-specificity insect-pathogenic fungi that naturally only infect a single or very few host species. The extent to which insect-pathogenic fungi in the order Entomophthorales rely on SLSPs is unknown. Here we take advantage of recently available transcriptomic and genomic datasets from four genera within Entomophthoromycotina: the saprobic or opportunistic pathogens Basidiobolus meristosporus, Conidiobolus coronatus, C. thromboides, C. incongruus, and the host-specific insect pathogens Entomphthora muscae and Pandora formicae, specific pathogens of house flies (Muscae domestica) and wood ants (Formica polyctena), respectively. We use phylogenetics and protein domain analysis to show that the obligate biotrophic fungi E. muscae, P. formicae and the saprobic human pathogen C. incongruus all contain “classical” fungal SLSPs and a unique group of SLSPs that loosely resembles bacillopeptidase F-like SLSPs. This novel group of SLSPs is found in the genomes of obligate insect pathogens and a generalist saprobic opportunistic pathogen why they are unlikely to be responsible for the host specificity of Entomophthorales. However, this class represent a unique group of SLSPs so far only observed among Bacteria, Oomycetes and early diverging fungi such as Cryptomycota, Microsporidia, and Entomophthoromycotina and missing in the sister fungal lineages of Kickxellomycotina or the fungal phyla Mucoromyocta, Ascomycota and Basidiomycota fungi suggesting interesting gene loss patterns.

Intestinal Microsporidiosis

2001 ◽  
Vol 7 (S2) ◽  
pp. 170-171
Author(s):  
Jan Marc Orenstein
Keyword(s):  
Cell Wall ◽  
New Species ◽  
Opportunistic Pathogen ◽  
Enterocytozoon Bieneusi ◽  
New Genera ◽  
Polar Tube ◽  
Unique Structure ◽  
Intestinal Pathogens ◽  
Intestinal Microsporidiosis ◽  
Hiv Aids

Sixteen years have passed since a microsporidian was first reported as an opportunistic pathogen in HIV/AIDS. to date, two new genera, Enterocytozoon and Trachipleistophora, and 5 new species, Enterocytozoon bieneusi, Encephalitozoon hellem and E. intestinalis, and T. hominis and T. anthropophthera have been described infecting patients with AIDS. E. bieneusi and E. intestinalis have been among the most common intestinal pathogens diagnosed as causes of diarrhea and wasting in HIV/AIDS.Members of their phylum, Microspora, have in common a hollow polar tube that is tightly wound up in their spores. The coiling up of the polar tube, just beneath the cell wall, allows a structure that is several times its length to be packaged within a spore. E. bieneusi, which has the smallest of all microsporidian spores, 1 x 1.5 ¼m, overcomes its size limitations by packaging its polar tube in 2 layers of 3 coils each. When conditions are right, this unique structure is extruded from the spore and becomes the “needle of a syringe”.

Habitat Association of Klebsiella Species

1985 ◽  
Vol 6 (2) ◽  
pp. 52-58 ◽  
Author(s):  
Susan T. Bagley
Keyword(s):  
Drinking Water ◽  
Gastrointestinal Tract ◽  
Surface Waters ◽  
Industrial Effluents ◽  
Opportunistic Pathogen ◽  
Habitat Associations ◽  
Habitat Association ◽  
Klebsiella Species ◽  
Almost All ◽  
Polluted Waters

AbstractThe genus Klebsiella is seemingly ubiquitous in terms of its habitat associations. Klebsiella is a common opportunistic pathogen for humans and other animals, as well as being resident or transient flora (particularly in the gastrointestinal tract). Other habitats include sewage, drinking water, soils, surface waters, industrial effluents, and vegetation. Until recently, almost all these Klebsiella have been identified as one species, ie, K. pneumoniae. However, phenotypic and genotypic studies have shown that “K. pneumoniae” actually consists of at least four species, all with distinct characteristics and habitats. General habitat associations of Klebsiella species are as follows: K. pneumoniae—humans, animals, sewage, and polluted waters and soils; K. oxytoca—frequent association with most habitats; K. terrigena— unpolluted surface waters and soils, drinking water, and vegetation; K. planticola—sewage, polluted surface waters, soils, and vegetation; and K. ozaenae/K. rhinoscleromatis—infrequently detected (primarily with humans).

The In Vitro Antibiofilm Activity of Water Leaf Extract of Papaya (Carica papaya L.) against Pseudomonas aeruginosa

2017 ◽  
Vol 2 (3) ◽  
pp. 150-163
Author(s):  
Ekajayanti Kining ◽  
Syamsul Falah ◽  
Novik Nurhidayat
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Contact Time ◽  
Cell Attachment ◽  
Water Extract ◽  
Opportunistic Pathogen ◽  
Bacterial Biofilm ◽  
Antibiofilm Activity ◽  
Bacterial Survival ◽  
Optimum Conditions

Pseudomonas aeruginosa is one of opportunistic pathogen forming bacterial biofilm. The biofilm sustains the bacterial survival and infections. This study aimed to assess the activity of water extract of papaya leaves on inhibition of cells attachment, growth and degradation of the biofilm using crystal violet (CV) biofilm assay. Research results showed that water extract of papaya leaves contains alkaloids, tanins, flavonoids, and steroids/terpenoids and showed antibacterial activity and antibiofilm against P. aeruginosa. Addition of extract can inhibit the cell attachment and was able to degrade the biofilm of 40.92% and 48.058% respectively at optimum conditions: extract concentration of 25% (v/v), temperature 37.5 °C and contact time 45 minutes. With a concentration of 25% (v/v), temperature of 50 °C and the contact time of 3 days, extract of papaya leaves can inhibit the growth of biofilms of 39.837% v/v.

Three new species, two new genera, and new family Biphragmosagittidae (Сhaetognatha) from Southwest Pacific Ocean

2011 ◽  
Vol 20 (1) ◽  
pp. 161-173
Author(s):  
A.P. Kassatkina
Keyword(s):  
New Species ◽  
Type Species ◽  
Morphological Characters ◽  
The Body ◽  
New Order ◽  
New Genera ◽  
New Family ◽  
The Family ◽  
Three New Species

Resuming published and own data, a revision of classification of Chaetognatha is presented. The family Sagittidae Claus & Grobben, 1905 is given a rank of subclass, Sagittiones, characterised, in particular, by the presence of two pairs of sac-like gelatinous structures or two pairs of fins. Besides the order Aphragmophora Tokioka, 1965, it contains the new order Biphragmosagittiformes ord. nov., which is a unique group of Chaetognatha with an unusual combination of morphological characters: the transverse muscles present in both the trunk and the tail sections of the body; the seminal vesicles simple, without internal complex compartments; the presence of two pairs of lateral fins. The only family assigned to the new order, Biphragmosagittidae fam. nov., contains two genera. Diagnoses of the two new genera, Biphragmosagitta gen. nov. (type species B. tarasovi sp. nov. and B. angusticephala sp. nov.) and Biphragmofastigata gen. nov. (type species B. fastigata sp. nov.), detailed descriptions and pictures of the three new species are presented.

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