Publications by authors named "Trina Guerra"

The prevalence of was assessed in 117 triatomine insects from central Texas. The PCR-based results revealed in 59% of the insects (62 adults and eight nymphs), with overall prevalences of of 0% (0/9), 64% (11/17), 58% (10/17), 73% (30/41), and 57% (19/33) for the Bastrop, Caldwell, Gonzales, Guadalupe, and Hays counties, respectively. Analyses of 18S rRNA fragments confirmed in 81% of these samples.

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Strains CN4, CN6, CN7 and CNm7 were isolated from root nodules of from Murree in Pakistan. They do not form root nodules on nor on although they deformed root hairs of . The colonies are bright red-pigmented, the strains form hyphae and sporangia but no N-fixing vesicles and do not fix nitrogen .

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Two primer set/probe combinations targeting variable regions on the 23S rRNA gene were designed to detect and quantify chlamydiae in DNA extracted from brain swabs of the endangered Houston toad (Anaxyrus houstonensis) using SYBRGreen- and Taqman-based quantitative polymerase chain reaction (qPCR). Prevalence and abundance values for samples were generally different between SYBRGreen- and Taqman-based detection methods, with higher specificity observed for Taqman-based detection. Of the 314 samples analyzed, initial screening with SYBRGreen-based qPCR retrieved 138 positive samples, of which 52 were confirmed by Taqman-based analyses as chlamydiae.

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strain Ag45/Mut15 was isolated from a root nodule of growing in a swamp at lake Grossensee, Germany. The strain forms root nodules on , in which it produces hyphae and clusters of N-fixing vesicles. N-fixing vesicles are also produced in nitrogen-free growth medium, in addition to hyphae and sporangia.

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The genomes of two nitrogen-fixing strains, AiPa1 and AiPs1, are described as representatives of two novel candidate species Both strains were isolated from root nodules of , used as capture plants in bioassays on soils from a reforested site at Karttula, Finland, that was devoid of actinorhizal plants but contained 25 year-old monocultures of spruce ( (L.) Karsten) or pine ( L.), respectively.

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The sp. strain R82 genome is described as representative of a novel candidate species within cluster 1, as indicated by average nucleotide identity (ANI) analyses, with its closest relatives being Frankia nodulisporulans AgTrs and strains Ag45/Mut15 and AgPM24 (86% identity).

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The genomes of two nitrogen-fixing strains, AgB32 and AgKG'84/4, were isolated from spore-containing (spore+) and spore-free (spore-) root nodules of , but they did not sporulate upon reinfection. The two strains are described as representatives of two novel candidate species Phylogenomic and ANI analyses indicate that each strain represents a novel species within cluster 1, with genome sizes of 6.3 and 6.

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Illumina-based 16S rRNA V3 amplicon sequencing of total DNA obtained from soft tissue lesions (joint granulomas) of the endangered Houston toad (Anaxyrus houstonensis) demonstrated that many reads represented members of the actinobacterial Mycobacterium chelonae-abscessus complex. In order to quantify members of this complex in those lesions, we designed three complex-specific primer set/probe combinations (sets I, II and III) targeting variable regions on the 23S rRNA gene for SybrGreen- and Taqman-based quantitative polymerase chain reaction (qPCR). Both SybrGreen- and Taqman-based analyses specifically detected members of the M.

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The genomes of two nitrogen-fixing strains, Ag45/Mut15 and AgPM24, isolated from root nodules of are described as representatives of a novel candidate species Phylogenomic and ANI analyses confirmed that both strains are related to cluster 1 frankiae, and that both strains belong to a novel species. At 6.4 - 6.

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The effect of host plants on the abundance and distribution of introduced and indigenous Frankia populations was assessed in soils and root nodules of four alder species, Alnus glutinosa,Alnus cordata,Alnus rubra and Alnus viridis. Plants were grown in microcosms with either a sandy soil without detectable frankiae, with or without inoculation of a mixture of Frankia isolates, or a silty clay loam soil with indigenous Frankia. The presence of frankiae in soils increased plant height and root nodule formation, with significant increases in the presence of indigenous frankiae.

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In this study, we describe the genomes of two novel candidate species of non-nitrogen fixing that were isolated from the root nodules of and , genospecies CN and Ag, respectively Comparative genomic analyses revealed that both genospecies lack genes essential for nitrogen-fixation and possess genes involved in the degradation of plant cell walls. Additionally, we found distinct biosynthetic gene clusters in each genospecies. The availability of these genomes will contribute to the study of the taxonomy and evolution of actinorhizal symbioses.

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Head-starting of the federally endangered Houston toad (Anaxyrus houstonensis), that is, the release of egg strands, tadpoles, and metamorphic juveniles produced in captivity into the original breeding ponds, requires assessment of potential threats for the transmission of pathogens from captive to free-ranging toads. We used Illumina-based 16S rRNA V3 amplicon sequencing to investigate the community structure of bacteria from skin lesions of captive Houston toad and habitat (pond) samples. Proteobacteria, alone or together with Actinobacteria and, in some samples, Cyanobacteria represented virtually all reads in tissue lesion samples, whereas pond samples were much more diverse, with Acidobacteria, Actinobacteria, Bacteriodetes, Chloroflexi, Cyanobacteria, Firmicutes, Planctomycetes, Proteobacteria, and Verrucomicrobia present with little variation between samples.

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Leptospirosis, an emerging infectious disease caused by bacteria of the genus Leptospira, is thought to be the most widespread zoonotic disease in the world. A first step in preventing the spread of Leptospira is delineating the animal reservoirs that maintain and disperse the bacteria. Quantitative PCR (qPCR) methods targeting the LipL32 gene were used to analyze kidney samples from 124 House mice (Mus musculus), 94 Black rats (Rattus rattus), 5 Norway rats (R.

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The prevalence of salmonellae in the intestines of the invasive suckermouth catfish Hypostomus plecostomus was assessed in the San Marcos River, just down-stream of its spring-fed headwaters. In 2014, H. plecostomus, sediment, and water samples were collected during 15 sampling events.

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Actinorhizal plants form nitrogen-fixing root nodules in symbiosis with soil-dwelling actinobacteria within the genus , and specific taxonomic clusters nodulate plants in corresponding host infection groups. In same-soil microcosms, we observed that some host species were nodulated (, , , ) while others were not (, ). Nodule populations were represented by eight different sequences of gene fragments.

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Rodent species were assessed as potential hosts of Trypanosoma cruzi, the etiologic agent of Chagas disease, from five sites throughout Texas in sylvan and disturbed habitats. A total of 592 rodents were captured, resulting in a wide taxonomic representation of 11 genera and 15 species. Heart samples of 543 individuals were successfully analyzed by SybrGreen-based quantitative PCR (qPCR) targeting a 166 bp fragment of satellite DNA of T.

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The nodule-forming actinobacterial genus can generally be divided into 4 taxonomic clusters, with clusters 1, 2, and 3 representing nitrogen-fixing strains of different host infection groups and cluster 4 representing atypical, generally non-nitrogen-fixing strains. Recently, quantitative PCR (qPCR)-based quantification methods have been developed for frankiae of clusters 1 and 3; however, similar approaches for clusters 2 and 4 were missing. We amended a database of partial 23S rRNA gene sequences of strains belonging to clusters 1 and 3 with sequences of frankiae representing clusters 2 and 4.

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Targeted Illumina sequencing of nitrogenase reductase (nifH) gene fragments and analyses of pair-end reads through a modified QIIME pipeline were used to assess the diversity of the actinomyceteous genus Frankia in three soils. Soils were vegetated with host or non-host plants, and included locations in Illinois (ABA, host), Colorado (CoMt, non-host), and Wisconsin (FMWI, non-host). After filtering, seven unique sequences were recovered for soil ABA, six for CoMt, and four sequences for FMWI.

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Somatic cell nuclear transfer (SCNT), or cloning, is one of the assisted reproductive technologies currently used in agriculture. Commercial applications of SCNT are presently limited to the production of animals of high genetic merit or the production of the most elite show cattle owing to its relatively low efficiency. In current practice, 20% to 40% of SCNT pregnancies do not result in viable offspring.

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To expedite linkage studies and positional cloning efforts in the dog, Minimal Screening Set 2 (MSS-2) of 327 canine microsatellite markers has been multiplexed into chromosome-specific panels. MSS-2 provides 9 Mb coverage of the canine genome with no gaps larger than 17.1 Mb and is the most recent and comprehensive set of microsatellites available for whole-genome scans.

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