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Pseudomonas fluorescens is known to have the ability to adhere and produce biofilm. The formation of biofilms is enhanced by cellular motility, particularly when mediated by flagella. Biofilm formed on surfaces such as those used for food production act as points of contamination, releasing pathogenic or deteriorating microorganisms and compromising the quality of products. We assessed two strains of Pseudomonas fluorescens PL5.4 and PL7.1, sampled from raw, chilled, buffalo milk, which was obtained from a dairy farm. Twitching and swarming motility assays were performed, in addition to the biofilm production evaluations at a temperature of 7 °C. Regarding the motility assays, only the PL5.4 strain scored positive for the swarming assay. On microplates, both strains presented themselves as strong biofilm producers at 7 °C. The PL5.4 strain was also able to form biofilm on a stainless steel structure and maintain this structure for up to 72 hours at refrigeration. The Pseudomonas fluorescens PL5.4 isolate was identified on the basis of a 99% sequence identity with Pseudomonas fluorescens A506, a strain used as a biocontrol in agriculture. Biofilm-forming bacteria, when adapted to low temperatures, become a constant source of contamination, damaging the production, quality, safety and shelf-life of products.

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This study emphasizes the importance of monitoring the microbiological quality of animal products, such as raw sheep's milk and cheese, to ensure food safety. In Brazil, there is currently no legislation governing the quality of sheep's milk and its derivatives. Therefore, this study aimed to evaluate: (i) the hygienic-sanitary quality of raw sheep's milk and cheese produced in southern Brazil; (ii) the presence of enterotoxins and Staphylococcus spp. in these products; and (iii) the susceptibility of the isolated Staphylococcus spp. to antimicrobial drugs and the presence of resistance genes. A total of 35 samples of sheep's milk and cheese were examined. The microbiological quality and presence of enterotoxins were accessed using Petrifilm and VIDAS SET2 methods, respectively. Antimicrobial susceptibility tests were conducted using VITEK 2 equipment and the disc diffusion method. The presence of resistance genes tet(L), sul1, sul2, ermB, tetM, AAC(6)', tetW, and strA were evaluated through PCR. In total, 39 Staphylococcus spp. were obtained. The resistance genes tetM, ermB, strA, tetL, sul1, AAC(6)', and sul2 were detected in 82%, 59%, 36%, 28%, 23%, 3%, and 3% of isolates, respectively. The findings revealed that both raw sheep's milk and cheese contained Staphylococcus spp. that exhibited resistance to antimicrobial drugs and harbored resistance genes. These results underscore the immediate need for specific legislation in Brazil to regulate the production and sale of these products.

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Bovine alphaherpesvirus 5 causes meningoencephalitis in cattle, belongs to the Herpesviridae family, and can be divided into subtypes a, b, and c. Limited information is available about subtype c. Here, we report the complete genome sequences of two strains, P160/96, and ISO97/45, isolated from cattle in southeast Brazil.

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BACKGROUND: Gut microbiota-derived short-chain fatty-acid (SFCA) acetate protects mice against RSV A2 strain infection by increasing interferon-ß production and expression of interferon-stimulated genes (ISGs). However, the role of SFCA in RSV infection using strains isolated from patients is unknown. METHODS: We first used RSV clinical strains isolated from infants hospitalized with RSV bronchiolitis to investigate the effects of in vitro SCFA-acetate treatment of human pulmonary epithelial cells. We next examined whether SCFA-acetate treatment is beneficial in a mouse model of RSV infection using clinical isolates. We sought to investigate the relationship of gut microbiota and fecal acetate with disease severity among infants hospitalized with RSV bronchiolitis, and whether treating their respiratory epithelial cells with SCFA-acetate ex-vivo impacts viral load and ISG expression. We further treated epithelial cells from SARS-CoV-2 infected patients with SCFA-acetate. FINDINGS: In vitro pre-treatment of A549 cells with SCFA-acetate reduced RSV infection with clinical isolates and increased the expression of RIG-I and ISG15. Animals treated with SCFA-acetate intranasally recovered significantly faster, with reduction in the RSV clinical isolates viral load, and increased lung expression of IFNB1 and the RIG-I. Experiments in RIG-I knockout A549 cells demonstrated that the protection relies on RIG-I presence. Gut microbial profile was associated with bronchiolitis severity and with acetate in stool. Increased SCFA-acetate levels were associated with increasing oxygen saturation at admission, and shorter duration of fever. Ex-vivo treatment of patients' respiratory cells with SCFA-acetate reduced RSV load and increased expression of ISGs OAS1 and ISG15, and virus recognition receptors MAVS and RIG-I, but not IFNB1. These SCFA-acetate effects were not found on cells from SARS-CoV-2 infected patients. INTERPRETATION: SCFA-acetate reduces the severity of RSV infection and RSV viral load through modulation of RIG-I expression. FUNDING: FAPERGS (FAPERGS/MS/CNPq/SESRS no. 03/2017 - PPSUS 17/2551-0001380-8 and COVID-19 20/2551-0000258-6); CNPq 312504/2017-9; CAPES) - Finance Code 001.

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The subfamily Parvovirinae within the family Parvoviridae consists of viruses that can infect a wide range of vertebrate hosts and cause effects ranging from severe disease to asymptomatic infection. In the present study, high-throughput sequencing (HTS) was utilized to analyze samples obtained from an abortion outbreak in a sheep flock to identify a putative viral etiology. A highly divergent nearly complete parvovirid genome sequence, approximately 4.9 kb in length, was determined. The nonstructural protein (NS1) amino acid (aa) sequence of this virus shared less than 30% identity with those of other copiparvoviruses and less than 22% identity with those of members of other genera in the subfamily Parvovirinae. Phylogenetically, this virus, which we have provisionally named "sheep copiparvovirus 1", formed a cluster with copiparvovirus sequences and should be classified as a member of a new species in the genus Copiparvovirus.

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Papillomaviruses (PVs) are circular double-stranded DNA virus belonging to Papillomaviridae family. During the infection cycle, PVs translate proteins that can influence cell growth and differentiation, leading to epidermal hyperplasia and papillomas (warts) or malignant neoplasms. Canis familiaris papillomaviruses (CPVs) have been associated with different lesions, such as oral and cutaneous papillomatosis, pigmented plaques, and squamous cell carcinomas (SCCs). Here, we report a clinical case of a mixed bred female dog with pigmented plaques induced by CPV16 (Chipapillomavirus 2) that progressed to in situ and invasive SCCs. Gross and histological findings were characterized, and the lesions were mainly observed in ventral abdominal region and medial face of the limbs. In situ hybridization (ISH) revealed strong nuclear hybridization signals in the neoplastic epithelial cells, as well as in the keratinocytes and koilocytes of the pigmented viral plaques. The full genome of the CPV16 recovered directly from the lesions was characterized, and the phylogenetic relationships were determined. The identification of oncoprotein genes (E5, E6, and E7) by high throughput sequencing (HTS) and their expected domains are suggestive of the malignant transformation by CPV16.

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Thirty-one bovine cutaneous warts were submitted to macroscopic and histological analyses and to molecular analyses to partial amplification and sequencing of the L1 gene of bovine papillomavirus (BPV). Viral types detected were BPV1 (52%), BPV2 (29%), BPV6 (16%) and BPV10 (3%). BPV2 had lower frequency in papilloma in comparison to that in fibropapilloma (p = 0.002).

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Bovine viral diarrhea virus 1, reclassified as Pestivirus A, causes an economically important cattle disease that is distributed worldwide. Pestivirus A may cause persistent infection in that calves excrete the virus throughout their lives, spreading the infection in the herd. Many persistently infected (PI) calves die in the first 2 years of life from mucosal disease (MD) or secondary infections, probably as a consequence of virus-induced immune depression. Here, high-throughput sequencing (HTS) was applied for evaluation of the total virome in sera of (i) PI calves displaying clinically apparent MD (n = 8); (ii) PI calves with no signs of MD (n = 8); and (iii) control, Pestivirus A-free calves (n = 8). All the groups were collected at the same time and from the same herd. Serum samples from calves in each of the groups were pooled, submitted to viral RNA/DNA enrichment, and sequenced by HTS. Viral genomes of Pestivirus A, Ungulate erythroparvovirus 1, bosavirus (BosV), and hypothetical circular Rep-encoding single-stranded DNA (CRESS-DNA) viruses were identified. Specific real-time PCR assays were developed to determine the frequency of occurrence of such viruses in each of the groups. The absolute number of distinct viral genomes detected in both PI calf groups was higher than in the control group, as revealed by higher number of reads, contigs, and genomes, representing a wider range of taxons. Genomes representing members of the family Parvoviridae, such as U. erythroparvovirus 1 and BosV, were most frequently detected in all the three groups of calves. Only in MD-affected PI calves, we found two previously unreported Hypothetical single-stranded DNA genomes clustered along with CRESS-DNA viruses. These findings reveal that parvoviruses were the most frequently detected viral genomes in cattle serum; its frequency of detection bears no statistical correlation with the status of calves in relation to Pestivirus A infection, since clinically normal or MD-affected/non-affected PI calves were infected with similar U. erythroparvovirus 1 genome loads. Moreover, MD-affected PI calves were shown to support viremia of CRESS-DNA viral genomes; however, the meaning of such correlation remains to be established.

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Here, we report the draft genome sequence of the yeast Spathaspora xylofermentans UFMG-HMD23.3 (=CBS 12681), a d-xylose-fermenting yeast isolated from the Amazonian forest. The genome consists of 298 contigs, with a total size of 15.1 Mb, including the mitochondrial genome, and 5,948 predicted genes.