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1.
Hig. Aliment. (Online) ; 38(298): e1144, jan.-jun. 2024.
Artículo en Portugués | LILACS, VETINDEX | ID: biblio-1531444

RESUMEN

As falhas na higienização em um estabelecimento de alimentos podem refletir em problemas causando a contaminação ou deterioração do produto produzido. Esta pesquisa foi motivada por reclamações de consumidores informando que os queijos apresentaram fungos, mesmo estando dentro do prazo de validade e por solicitação do Serviço de Inspeção Municipal. O objetivo desta pesquisa foi avaliar a contaminação ambiental em uma agroindústria da agricultura familiar produtora de queijo colonial no Sudoeste Paranaense. Foram realizadas a contagem para aeróbios mesófilos em equipamentos e superfícies que entram em contato com o alimento e análise microbiológica ambiental de bolores e leveduras na sala de secagem dos queijos. A coleta foi realizada com método de esfregaço de suabe estéril para aeróbios mesófilos e semeadas em placas de Petri com Ágar Padrão de Contagem. Para a coleta ambiental foram expostas placas de Petri com ágar Saboraund durante 15 minutos. Os resultados demonstraram ausência de contaminação nas superfícies, mas foram encontrados bolores e leveduras de forma acentuada na sala de secagem dos queijos, o que pode contribuir para a deterioração do produto, diminuindo sua validade. Para minimizar as perdas por contaminação é necessário que o processo de higienização dos ambientes seja realizado de forma eficiente.


Failures in hygiene in a food establishment can result in problems causing contamination or deterioration of the product produced. This research was motivated by complaints from consumers reporting that the cheeses had mold, even though they were within their expiration date and at the request of the Municipal Inspection Service. This research was to evaluate environmental contamination in an agroindustry in the family farm producing colonial cheese in Southwest Paraná. For the microbiological assessment of environmental contamination, counting for mesophilic aerobes was carried out on equipment and surfaces that come into contact with food and, environmental microbiological analysis of molds and yeast in the cheese drying room. The collection was carried out using the sterile swab smear for mesophilic aerobes and seeded in Petri dishes with Counting Standard Agar. For environmental collection, sheets of Petri with Saboraund agar for 15 minutes. The results demonstrated absence of contamination on surfaces. But the presence of molds and yeasts in the drying room cheeses, which can contribute to the deterioration of the product and thus reduce the validity. To minimize losses due to contamination, it is It is necessary that the process of cleaning and disinfecting environments is carried out efficiently.


Asunto(s)
Higiene Alimentaria , Queso/microbiología , Brasil , Buenas Prácticas de Fabricación , Enfermedades Transmitidas por los Alimentos/prevención & control
2.
iScience ; 27(4): 109457, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38558931

RESUMEN

Helicobacter pylori (H. pylori) infection is a known cause of many digestive diseases, including gastritis, peptic ulcers, and gastric cancer. However, the underlying mechanisms by which H. pylori infection triggers these disorders are still not clearly understood. Gastric cancer is a slow progressing disease, which makes it difficult to study. We have developed an accelerated disease progression mouse model, which leverages mice deficient in the myeloid differentiation primary response 88 gene (Myd88-/-) infected with Helicobacter felis (H. felis). Using this model and gastric biopsy samples from patients, we report that activation of the Toll/interleukin-1 receptor (TIR)-domain-containing adaptor inducing interferon-ß (TRIF)-type I interferon (IFN-I) signaling pathway promotes Helicobacter-induced disease progression toward severe gastric pathology and gastric cancer development. Further, results implicated downstream targets of this pathway in disease pathogenesis. These findings may facilitate stratification of Helicobacter-infected patients and thus enable treatment prioritization of patients.

3.
iScience ; 27(4): 109467, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38558939

RESUMEN

Alba domain proteins, owing to their functional plasticity, play a significant role in organisms. Here, we report an intrinsic DNase activity of PfAlba6 from Plasmodium falciparum, an etiological agent responsible for human malignant malaria. We identified that tyrosine28 plays a critical role in the Mg2+ driven 5'-3' DNase activity of PfAlba6. PfAlba6 cleaves both dsDNA as well as ssDNA. We also characterized PfAlba6-DNA interaction and observed concentration-dependent oligomerization in the presence of DNA, which is evident from size exclusion chromatography and single molecule AFM-imaging. PfAlba6 mRNA expression level is up-regulated several folds following heat stress and treatment with artemisinin, indicating a possible role in stress response. PfAlba6 has no human orthologs and is expressed in all intra-erythrocytic stages; thus, this protein can potentially be a new anti-malarial drug target.

4.
Front Microbiol ; 15: 1334897, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38562474

RESUMEN

In recent years, the automatic machine for microbial identification and antibiotic susceptibility tests has been introduced into the microbiology laboratory of our hospital, but there are still many steps that need manual operation. The purpose of this study was to establish an auto-verification system for bacterial naming to improve the turnaround time (TAT) and reduce the burden on clinical laboratory technologists. After the basic interpretation of the gram staining results of microorganisms, the appearance of strain growth, etc., the 9 rules were formulated by the laboratory technologists specialized in microbiology for auto-verification of bacterial naming. The results showed that among 70,044 reports, the average pass rate of auto-verification was 68.2%, and the reason for the failure of auto-verification was further evaluated. It was found that the main causes reason the inconsistency between identification results and strain appearance rationality, the normal flora in the respiratory tract and urine that was identified, the identification limitation of the mass spectrometer, and so on. The average TAT for the preliminary report of bacterial naming was 35.2 h before, which was reduced to 31.9 h after auto-verification. In summary, after auto-verification, the laboratory could replace nearly 2/3 of manual verification and issuance of reports, reducing the daily workload of medical laboratory technologists by about 2 h. Moreover, the TAT on the preliminary identification report was reduced by 3.3 h on average, which could provide treatment evidence for clinicians in advance.

5.
Cell Rep ; 43(4): 114051, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38564334

RESUMEN

Uropathogenic Escherichia coli (UPEC) is the most common causative agent of urinary tract infection (UTI). UPEC invades bladder epithelial cells (BECs) via fusiform vesicles, escapes into the cytosol, and establishes biofilm-like intracellular bacterial communities (IBCs). Nucleoside-diphosphate kinase (NDK) is secreted by pathogenic bacteria to enhance virulence. However, whether NDK is involved in UPEC pathogenesis remains unclear. Here, we find that the lack of ndk impairs the colonization of UPEC CFT073 in mouse bladders and kidneys owing to the impaired ability of UPEC to form IBCs. Furthermore, we demonstrate that NDK inhibits caspase-1-dependent pyroptosis by consuming extracellular ATP, preventing superficial BEC exfoliation, and promoting IBC formation. UPEC utilizes the reactive oxygen species (ROS) sensor OxyR to indirectly activate the regulator integration host factor, which then directly activates ndk expression in response to intracellular ROS. Here, we reveal a signaling transduction pathway that UPEC employs to inhibit superficial BEC exfoliation, thus facilitating acute UTI.

6.
RNA ; 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38565243

RESUMEN

RNA thermometers are highly structured noncoding RNAs located in the 5' untranslated regions (UTR) of genes that regulate expression by undergoing conformational changes in response to temperature. The discovery of RNA thermometers through bioinformatics is difficult because there is little sequence conservation among their structural elements. Thus, the abundance of these thermo-sensitive regulatory structures remains unclear. Herein, to advance the discovery and validation of RNA thermometers, we developed Robo-Therm, a pipeline that combines an adaptive and user-friendly in silico motif search with a well-established reporter system. Through our application of Robo-Therm, we discovered two novel RNA thermometers in bacterial and bacteriophage genomes found in the human gut. One of these thermometers is present in 5'-UTR of a gene that codes for σ70 RNA polymerase subunit in the bacteria Mediterraneibacter gnavus and Bacteroides pectinophilus, and in the bacteriophage Caudoviricetes, which infects Bacteroides pectinophilus. The other thermometer is in the 5'-UTR of a tetracycline resistance gene (tetR) in the intestinal bacteria Escherichia coli and Shigella flexneri. Our Robo-Therm pipeline can be applied to discover multiple RNA thermometers across various genomes.

7.
Foodborne Pathog Dis ; 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38568114

RESUMEN

Escherichia coli O157:H7 (E. coli O157:H7) and Campylobacter jejuni (C. jejuni) are pathogenic microorganisms that can cause severe clinical symptoms in humans and are associated with bovine meat consumption. Specific monitoring for E. coli O157: H7 or C. jejuni in meat is not mandatory under Chilean regulations. In this study, we analyzed 544 samples for the detection of both microorganisms, obtained from 272 bovine carcasses (280 kg average) at two slaughterhouses in the Bio-Bío District, Chile. Sampling was carried out at post-shower of carcasses and after channel passage through the cold chamber. Eleven samples were found to be positive for E. coli O157:H7 (4.0%) using microbiological and biochemical detection techniques and were subjected to a multiplex PCR to detect fliC and rfbE genes. Six samples (2.2%) were also found to be positive for the pathogenicity genes stx1, stx2, and eaeA. Twenty-two carcasses (8.0%) were found to be positive for C. jejuni using microbiological and biochemical detection techniques, but no sample with amplified mapA gene was found.

8.
Artículo en Inglés | MEDLINE | ID: mdl-38558338

RESUMEN

With the extensive development of nuclear energy, soil uranium contamination has become an increasingly prominent problem. The development of evaluation systems for various uranium contamination levels and soil microhabitats is critical. In this study, the effects of uranium contamination on the carbon source metabolic capacity and microbial community structure of soil microbial communities were investigated using Biolog microplate technology and high-throughput sequencing, and the responses of soil biochemical properties to uranium were also analyzed. Then, ten key biological indicators as reliable input variables, including arylsulfatase, biomass nitrogen, metabolic entropy, microbial entropy, Simpson, Shannon, McIntosh, Nocardioides, Lysobacter, and Mycoleptodisus, were screened by random forest (RF), Boruta, and grey relational analysis (GRA). The optimal uranium-contaminated soil microbiological evaluation model was obtained by comparing the performance of three evaluation methods: partial least squares regression (PLS), support vector regression (SVR), and improved particle algorithm (IPSO-SVR). Consequently, partial least squares regression (PLS) has a higher R2 (0.932) and a lower RMSE value (0.214) compared to the other. This research provides a new evaluation method to describe the relationship between soil ecological effects and biological indicators under nuclear contamination.

9.
Microbiol Resour Announc ; : e0065623, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38563745

RESUMEN

Here, we present genome sequences of five Stenotrophomonas indicatrix strains, isolated from agricultural soil. Stenotrophomonas strains are commonly associated with the rhizosphere and are well-known for their ability to degrade xenobiotics. Yet, to date, knowledge about S. indicatrix is limited.

10.
Elife ; 122024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38568203

RESUMEN

Natural environments of living organisms are often dynamic and multifactorial, with multiple parameters fluctuating over time. To better understand how cells respond to dynamically interacting factors, we quantified the effects of dual fluctuations of osmotic stress and glucose deprivation on yeast cells using microfluidics and time-lapse microscopy. Strikingly, we observed that cell proliferation, survival, and signaling depend on the phasing of the two periodic stresses. Cells divided faster, survived longer, and showed decreased transcriptional response when fluctuations of hyperosmotic stress and glucose deprivation occurred in phase than when the two stresses occurred alternatively. Therefore, glucose availability regulates yeast responses to dynamic osmotic stress, showcasing the key role of metabolic fluctuations in cellular responses to dynamic stress. We also found that mutants with impaired osmotic stress response were better adapted to alternating stresses than wild-type cells, showing that genetic mechanisms of adaptation to a persistent stress factor can be detrimental under dynamically interacting conditions.


Asunto(s)
Osmorregulación , Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Presión Osmótica , Proliferación Celular , Glucosa
11.
Cell Rep ; 43(4): 114029, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38573852

RESUMEN

The host-microbiota relationship has evolved to shape mammalian physiology, including immunity, metabolism, and development. Germ-free models are widely used to study microbial effects on host processes such as immunity. Here, we find that both germ-free and T cell-deficient mice exhibit a robust sebum secretion defect persisting across multiple generations despite microbial colonization and T cell repletion. These phenotypes are inherited by progeny conceived during in vitro fertilization using germ-free sperm and eggs, demonstrating that non-genetic information in the gametes is required for microbial-dependent phenotypic transmission. Accordingly, gene expression in early embryos derived from gametes from germ-free or T cell-deficient mice is strikingly and similarly altered. Our findings demonstrate that microbial- and immune-dependent regulation of non-genetic information in the gametes can transmit inherited phenotypes transgenerationally in mice. This mechanism could rapidly generate phenotypic diversity to enhance host adaptation to environmental perturbations.

12.
Cell Rep ; 43(4): 114012, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38573856

RESUMEN

Plasmodium falciparum is a human-adapted apicomplexan parasite that causes the most dangerous form of malaria. P. falciparum cysteine-rich protective antigen (PfCyRPA) is an invasion complex protein essential for erythrocyte invasion. The precise role of PfCyRPA in this process has not been resolved. Here, we show that PfCyRPA is a lectin targeting glycans terminating with α2-6-linked N-acetylneuraminic acid (Neu5Ac). PfCyRPA has a >50-fold binding preference for human, α2-6-linked Neu5Ac over non-human, α2-6-linked N-glycolylneuraminic acid. PfCyRPA lectin sites were predicted by molecular modeling and validated by mutagenesis studies. Transgenic parasite lines expressing endogenous PfCyRPA with single amino acid exchange mutants indicated that the lectin activity of PfCyRPA has an important role in parasite invasion. Blocking PfCyRPA lectin activity with small molecules or with lectin-site-specific monoclonal antibodies can inhibit blood-stage parasite multiplication. Therefore, targeting PfCyRPA lectin activity with drugs, immunotherapy, or a vaccine-primed immune response is a promising strategy to prevent and treat malaria.

13.
Microbiol Spectr ; : e0367423, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38578091

RESUMEN

Vibrio is a genus of halophilic, gram-negative bacteria found in estuaries around the globe. Integral parts of coastal cultures often involve contact with vectors of pathogenic Vibrio spp. (e.g., consuming raw shellfish). High rates of mortality from certain Vibrio spp. infections demonstrate the need for an improved understanding of Vibrio spp. dynamics in estuarine regions. Our study assessed meteorological, hydrographic, and biological correlates of Vibrio parahaemolyticus and V. vulnificus at 10 sites in the Eastern Mississippi Sound System (EMSS) from April to October 2019. During the sampling period, median abundances of V. parahaemolyticus and V. vulnificus were 2.31 log MPN/L and 2.90 log MPN/L, respectively. Vibrio spp. dynamics were largely driven by site-based variation, with sites closest to freshwater inputs having the highest abundances. The E-W wind scalar, which affects Ekman transport, was a novel Vibrio spp. correlate observed. A potential salinity effect on bacterial-particle associations was identified, where V. vulnificus was associated with larger particles in conditions outside of their optimal salinity. Additionally, V. vulnificus abundances were correlated to those of harmful algal species that did not dominate community chlorophyll. Correlates from this study may be used to inform the next iteration of regionally predictive Vibrio models and may lend additional insight to Vibrio spp. ecology in similar systems. IMPORTANCE: Vibrio spp. are bacteria found in estuaries worldwide; some species can cause illness and infections in humans. Relationships between Vibrio spp. abundance, salinity, and temperature are well documented, but correlations to other environmental parameters are less understood. This study identifies unique correlates (e.g., E-W wind scalar and harmful algal species) that could potentially inform the next iteration of predictive Vibrio models for the EMSS region. Additionally, these correlates may allow existing environmental monitoring efforts to be leveraged in providing data inputs for future Vibrio risk models. An observed correlation between salinity and V. vulnificus/particle-size associations suggests that predicted environmental changes may affect the abundance of Vibrio spp. in certain reservoirs, which may alter which vectors present the greatest vibrio risk.

14.
Vet World ; 17(2): 398-406, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38595673

RESUMEN

Background and Aim: A combined microbial and cytological examination of uterine samples is the main diagnostic method for endometritis in mares. This study aimed to describe a procedure for using the same uterine cytobrush (CB) for both bacteriological and cytological evaluation. Material and Methods: The procedure consists of rolling the CB onto a sterilized glass slide immediately after collection and before the transfer into a sterile saline solution. In Experiment 1, a comparison between bacteriological results of the cotton swab (CS) and CB or pellet was made in 10 mares; in Experiment 2, bacteriological and cytological results were compared between different processing methods of CB in 28 mares; in other 6 mares, a CB was processed for cytology only, to investigate the reasons for the low cellularity of the pellet. Results: The agreement between culture results from the CB and CS was evaluated, and a comparison between the cytological data obtained by different processing methods of CB was performed. The perfect agreement between the CB and CS microbiological results was found. The described procedure enables useful diagnostic smears for cytology. Moreover, the seeding of both the tip of CB and the saline solution used for the transport produced accurate bacteriological results. Conclusion: The protocol described in this study for the use of CB for both cytological and bacteriological analysis could be used for the diagnosis of endometritis. To maximize diagnostic sample quality, cytology slides must be prepared with meticulous care in the field to preserve cellular integrity and minimize artifacts.

15.
iScience ; 27(4): 109488, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38595798

RESUMEN

To further assess the spectrum of nanoarchaea in human microbiota, we prospectively searched for nanoarchaea in 110 leftover stool specimens, using the complementary approaches of PCR-sequencing screening, fluorescent in situ hybridization, scanning electron microscopy and metagenomics. These investigations yielded a nanoarchaea, Candidatus Nanopusillus phoceensis sp. nov., detected in stool samples by specific PCR-based assays. Microscopic observations indicated its close contact with the archaea Methanobrevibacter smithii. Genomic sequencing revealed 607,775-bp contig with 24.5% G + C content encoding 30 tRNAs, 3 rRNA genes, and 1,403 coding DNA sequences, of which 719 were assigned to clusters of orthologous groups. Ca. Nanopusillus phoceensis is only the second nanoarchaea to be detected in humans, expanding our knowledge of the repertoire of nanoarchaea associated with the human microbiota and encouraging further research to explore the repertoire of this emerging group of nanomicrobes in clinical samples.

16.
Cell Rep ; 43(4): 114078, 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38598334

RESUMEN

The vaginal microbiome's composition varies among ethnicities. However, the evolutionary landscape of the vaginal microbiome in the multi-ethnic context remains understudied. We perform a systematic evolutionary analysis of 351 vaginal microbiome samples from 35 multi-ethnic pregnant women, in addition to two validation cohorts, totaling 462 samples from 90 women. Microbiome alpha diversity and community state dynamics show strong ethnic signatures. Lactobacillaceae have a higher ratio of non-synonymous to synonymous polymorphism and lower nucleotide diversity than non-Lactobacillaceae in all ethnicities, with a large repertoire of positively selected genes, including the mucin-binding and cell wall anchor genes. These evolutionary dynamics are driven by the long-term evolutionary process unique to the human vaginal niche. Finally, we propose an evolutionary model reflecting the environmental niches of microbes. Our study reveals the extensive ethnic signatures in vaginal microbial ecology and evolution, highlighting the importance of studying the host-microbiome ecosystem from an evolutionary perspective.

17.
Water Res ; 256: 121492, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38593604

RESUMEN

Cyanobacterial blooms, producing toxic secondary metabolites, are becoming increasingly common phenomena in the face of rising global temperatures. They are the world's most abundant photosynthetic organisms, largely owing their success to a range of highly diverse and complex natural products possessing a broad spectrum of different bioactivities. Over 2600 compounds have been isolated from cyanobacteria thus far, and their characterisation has revealed unusual and useful chemistries and motifs including alkynes, halogens, and non-canonical amino acids. Genome sequencing of cyanobacteria lags behind natural product isolation, with only 19% of cyanobacterial natural products associated with a sequenced organism. Recent advances in meta(genomics) provide promise to narrow this gap and has also facilitated the uprise of combined genomic and metabolomic approaches, heralding a new era of discovery of novel compounds. Analyses of the datasets described within this manuscript reveal the asynchrony of current genomic and metabolomic data, highlight the chemical diversity of cyanobacterial natural products. Linked to this manuscript, we make these manually curated datasets freely accessible for the public to facilitate further research in this important area.

19.
Int J Legal Med ; 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38594499

RESUMEN

Forensic microbiology is rapidly emerging as a novel tool for human identification. The human microbiome, comprising diverse microbial communities including fungi, bacteria, protozoa, and viruses, is unique to each individual, offering a new dimension to forensic investigations. While traditional identification methods primarily rely on DNA profiling and fingerprint analysis, they face limitations when complete DNA or fingerprints profiles are unattainable or degraded. In this context, the microbial signatures of the human skin microbiome present a promising alternative due to their resilience to environmental stresses and individual-specific composition. This review explores the potential of microbiome analysis in forensic human identification, evaluating its applications, advantages, limitations, and future prospects. The uniqueness of an individual's microbial community, particularly the skin microbiota, can provide distinctive biological markers for identification purposes, while technological advancements like 16 S rRNA sequencing and metagenomic shotgun sequencing are enhancing the specificity of microbial identification, enabling detailed analysis of these complex ecological communities. Despite these promising findings, current research has not yet achieved a level of identification probability that could establish microbial analysis as a stand-alone evidence tool. Therefore, it is presently considered ancillary to traditional methods, contributing to a more comprehensive biological profile of individuals.

20.
J Biol Chem ; : 107276, 2024 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-38588805

RESUMEN

Sphingolipids are produced by nearly all eukaryotes where they play significant roles in cellular processes such as cell growth, division, programmed cell death, angiogenesis, and inflammation. While it was previously believed that sphingolipids were quite rare among bacteria, bioinformatic analysis of the recently identified bacterial sphingolipid synthesis genes suggests that these lipids are likely to be produced by a wide range of microbial species. The sphingolipid synthesis pathway consists of three critical enzymes. Serine palmitoyltransferase catalyzes the condensation of serine with palmitoyl-CoA (or palmitoyl-acyl carrier protein), ceramide synthase adds the second acyl chain, and a reductase reduces the ketone present on the long-chain base. While there is general agreement regarding the identity of these bacterial enzymes, the precise mechanism and order of chemical reactions for microbial sphingolipid synthesis is more ambiguous. Two mechanisms have been proposed. First, the synthesis pathway may follow the well characterized eukaryotic pathway in which the long-chain base is reduced prior to the addition of the second acyl chain. Alternatively, our previous work suggests that addition of the second acyl chain precedes the reduction of the long-chain base. To distinguish between these two models, we investigated the subcellular localization of these three key enzymes. We found that serine palmitoyltransferase and ceramide synthase are localized to the cytoplasm whereas the ceramide reductase is in the periplasmic space. This is consistent with our previously proposed model wherein the second acyl chain is added in the cytoplasm prior to export to the periplasm where the lipid molecule is reduced.

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