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991.
N.T. Nguyen M. Liu H. Katayama T. Takemura I. Kasuga 《Letters in applied microbiology》2021,72(3):275-282
Colistin is one of the antibiotics of last resort for human health. However, the dissemination of the plasmid-mediated colistin resistance gene mcr-1 is of great concern globally. In the One Health framework, the environment is an important component for managing antimicrobial resistance. However, little information is available concerning the prevalence of mcr-1 in water environments. We aimed to reveal the prevalence of mcr-1 in different water environments in Hanoi, Vietnam. Quantitative PCR was applied to detect mcr-1 in four urban drainages receiving untreated domestic wastewater, three rivers, five lakes and two groundwater samples. Urban drainages contained higher concentrations of mcr-1, suggesting that urban residents carry the gene. The class 1 integron-integrase gene was identified as a good surrogate of antibiotic resistance genes including mcr-1. A significant correlation was found between the levels of mcr-1 and the human-specific cross-assembly phage, which is an indicator of human faecal pollution. These results indicated that the primary source of mcr-1 in urban water environments is human faeces, which is consistent with the fact that most domestic wastewater is untreated in Hanoi. The control of untreated wastewater is critical for alleviating the spread of mcr-1 in water environments in Vietnam. 相似文献
992.
N. Yamada W. Murata Y. Yamaguchi K.-I. Fujita A. Ogita T. Tanaka 《Letters in applied microbiology》2021,72(4):390-398
Amphotericin B (AmB), a typical polyene macrolide antifungal agent, is widely used to treat systemic mycoses. In the present study, we show that the fungicidal activity of AmB was enhanced by benzyl isothiocyanate (BITC), a cruciferous plant-derived compound, in the budding yeast, Saccharomyces cerevisiae. In addition to forming a molecular complex with ergosterol present in fungal cell membranes to form K+-permeable ion channels, AmB has been recognized to mediate vacuolar membrane disruption resulting in lethal effects. BITC showed no effect on AmB-induced plasma membrane permeability; however, it amplified AmB-induced vacuolar membrane disruption in S. cerevisiae. Furthermore, the BITC-enhanced fungicidal effects of AmB significantly decreased cell viability due to the disruption of vacuoles in the pathogenic fungus Candida albicans. The application of the combinatorial antifungal effect of AmB and BITC may aid in dose reduction of AmB in clinical antifungal therapy and consequently decrease side effects in patients. These results also have significant implications for the development of vacuole-targeting chemotherapy against fungal infections. 相似文献
993.
L.E. Palma-Cano H.A. Piñon-Castillo S.H. Tarango-Rivero A. Carbon J. Salas-Leiva L.N. Muñoz-Castellanos C. Cravo-Laureau R. Duran E. Orrantia-Borunda 《Letters in applied microbiology》2021,72(5):556-569
We described the bacterial diversity of walnut grove soils under organic and conventional farming. The bacterial communities of rhizospheric and nonrhizospheric soils of pecan tree (Carya illinoensis K. Koch) were compared considering two phenological stages (sprouting and ripening). Sixteen operational taxonomic units (OTUs) were identified significantly more abundant according to the plant development, only one according to the farming condition, and none according to the soil origin. The OTUs specificaly abundant according to plant development included Actinobateria (2) and Betaproteobacteria (1) related OTUs more abundant at the sprouting stage, while at the fruit ripening (FR) stage the more abundant OTUs were related to Actinobacteria (6), Alphaproteobacteria (6), and unclassified Bacteria (1). The Gaiellaceae OTU18 (Actinobacteria) was more abundant under conventional farming. Thus, our study revealed that the plant development stage was the main factor shaping the bacterial community structure, while less influence was noticed for the farming condition. The bacterial communities exhibited specific metabolic capacities, a large range of carbon sources being used at the FR stage. The identified OTUs specifically more abundant represent indicators providing useful information on soil condition, potential tools for the management of soil bacterial communities. 相似文献
994.
U. Schotte T. Hoffmann N.G. Schwarz S. Rojak J. Lusingu D. Minja J. Kaseka J. Mbwana S. Gesase J. May D. Dekker H. Frickmann 《Letters in applied microbiology》2021,72(6):774-782
The study was performed to compare real-time PCR after nucleic acid extraction directly from stool samples as well as from samples stored and transported on Whatman papers or flocked swabs at ambient temperature in the tropics. In addition, the possible suitability for a clear determination of likely aetiological relevance of PCR-based pathogen detections based on cycle threshold (Ct) values was assessed. From 632 Tanzanian children <5 years of age with and without gastrointestinal symptoms, 466 samples were subjected to nucleic acid extraction and real-time PCR for gastrointestinal viral, bacterial and protozoan pathogens. Equal or even higher frequencies of pathogen detections from Whatman papers or flocked swabs were achieved compared with nucleic acid extraction directly from stool samples. Comparison of the Ct values showed no significant difference according to the nucleic acid extraction strategy. Also, the Ct values did not allow a decision whether a detected pathogen was associated with gastrointestinal symptoms. 相似文献
995.
Improving the growth and pigment accumulation of microalgae by electrochemical approaches was considered a novel and promising method. In this research, we investigated the effect of conductive polymer poly (3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) dispersible in water on growth and pigment accumulation of Haematococcus lacustris and Euglena gracilis. The results revealed that effect of PEDOT:PSS was strongly cell-dependent and each cell type has its own peculiar response. For H. lacustris, the cell density in the 50 mg·l−1 treatment group increased by 50·27%, and the astaxanthin yield in the 10 mg·l−1 treatment group increased by 37·08%. However, under the high concentrations of PEDOT:PSS treatment, cell growth was significantly inhibited, and meanwhile, the smaller and more active zoospores were observed, which reflected the changes in cell life cycle and growth mode. Cell growth of E. gracilis in all the PEDOT:PSS treatment groups were notably inhibited. Chlorophyll a content in E. gracilis decreased while chlorophyll b content increased in response to the PEDOT:PSS treatment. The results laid a foundation for further development of electrochemical methods to promote microalgae growth and explore the interactions between conductive polymers and microalgae cells. 相似文献
996.
This study was conducted to isolate and identify extended-spectrum beta-lactamase (ESBL)-producing Enterobacterales in conventional and organic chicken meats, which were sold in Turkey. A total of 200 raw chicken meat sample (100 conventional and 100 organic) were used as material. Classic culture technique based on chromogenic method was used for the isolation of bacteria, and the identification was performed with VITEK MS. Phenotypic ESBL production was detected by combined disc diffusion method. Gene regions responsible for ESBL production were determined by PCR. MIC values of isolates were detected by VITEK 2. Phenotypic ESBL-producing Enterobacterales were detected in 46% of conventional chicken meats and in 22% of organic chicken meats. Of the 115 isolates obtained, 97 (84%) were Escherichia coli, 12 (10%) were Klebsiella pneumoniae, four (3·48%) were Serratia fonticola, one (0·87%) was Rahnella aquatilis, and one (0·87%) was Serratia liquefaciens. PCR analysis revealed that 109 of 115 isolates (94·78%) contained at least one of the blaCTX-M, blaTEM, and blaSHV genes. Of the 115 ESBL-producing isolates, 103 (89·57%) were found resistant to at least one antibiotic except for the β-lactam group. The contamination level of ESBL-producing Enterobacterales was higher in conventional chicken meats (P < 0·001). 相似文献
997.
K.L. Chew S. Octavia R. Jureen R.T.P. Lin J.W.P. Teo 《Letters in applied microbiology》2021,73(3):286-293
The objective of the study was to evaluate the use of targeted multiplex Nanopore MinION amplicon re-sequencing of key Candida spp. from blood culture bottles to identify azole and echinocandin resistance associated SNPs. Targeted PCR amplification of azole (ERG11 and ERG3) and echinocandin (FKS) resistance-associated loci was performed on positive blood culture media. Sequencing was performed using MinION nanopore device with R9.4.1 Flow Cells. Twenty-eight spiked blood cultures (ATCC strains and clinical isolates) and 12 prospectively collected positive blood cultures with candidaemia were included. Isolate species included Candida albicans, Candida glabrata, Candida krusei, Candida parapsilosis, Candida tropicalis and Candida auris. SNPs that were identified on ERG and FKS genes using Snippy tool and CLC Genomic Workbench were correlated with phenotypic testing by broth microdilution (YeastOne™ Sensititre). Illumina whole-genome-sequencing and Sanger-sequencing were also performed as confirmatory testing of the mutations identified from nanopore sequencing data. There was a perfect agreement of the resistance-associated mutations detected by MinION-nanopore-sequencing compared to phenotypic testing for acquired resistance (16 with azole resistance; 3 with echinocandin resistance), and perfect concordance of the nanopore sequence mutations to Illumina and Sanger data. Mutations with no known association with phenotypic drug resistance and novel mutations were also detected. 相似文献
998.
Condon Tom Hakim Abbas Moran Antonio B. Zenteno Blumstein Daniel T. 《Journal of Ethology》2021,39(1):89-96
Journal of Ethology - Animals emit predator-elicited calls in response to potential predation threats. These vocalizations induce a variety of anti-predator behaviors in conspecific receivers... 相似文献
999.
He Lijun Zhang Jinsha He Chengyun Zhao Boyang Chen Weizhong Patil Sunil R. 《Molecular and cellular biochemistry》2021,476(3):1599-1603
Molecular and Cellular Biochemistry - DNA hydroxymethylation plays a very important role in some biological processes, such as DNA methylation process. In addition, its presence can also cause some... 相似文献
1000.
Biogeochemistry - The coupling between chemical weathering (including silicate, carbonate and pyrite weathering) and physical erosion is of high interest in active mountain belts. Participation of... 相似文献