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1.
J Microbiol Biol Educ ; 24(2)2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37614900

RESUMO

We developed a course-based undergraduate research experience (CURE) that gives students an opportunity to practice the process of science in a context that intersects with their everyday lives: purchasing grocery store chicken. Student mastery of concepts was assessed by pre- and postassessment questions and lab report worksheets that guided them through the process of writing a scientific paper. Learning to produce graphs from large data sets and comparing the results with published data emphasized quantitative reasoning, while working as a group and writing helped students practice scientific communication. Most students (>90%) met the learning objectives, and students in both groups reported feeling more confident producing graphs and figures; they also showed large gains in confidence and interest in bioinformatics. Lab protocols require biosafety level 2 safety guidelines; however, students in an online or dry lab setting can use the compiled data sets and whole-genome sequences to complete the objectives. Group discussions and essay prompts at the end encourage students to use evidence-based arguments to make decisions that impact the global issue of antimicrobial resistance.

2.
J Microbiol Biol Educ ; 23(3)2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36532219

RESUMO

Since the start of the 2019 coronavirus disease (COVID-19) pandemic, many microbiology lab activities have been conducted online. We produced a simple PCR primer design and virtual PCR activity for introductory students to use as part of an online laboratory course or as an independent activity in a traditional laboratory setting. Most students are aware of basic PCR concepts but struggle with important details, such as how PCR is specific and how false positives and negatives can be generated in a diagnostic test that is not well designed. This exercise helps students review molecular biology concepts within the context of a test that was commonplace during the COVID-19 pandemic. We found that nursing students and Biology and non-Biology majors were able to complete the worksheet as a group with minimal instructor input. This could be used as a stand-alone activity, as a warm-up for other bioinformatics exercises, or as a prelab activity for actual in-lab quantitative PCR experiments, such as the one offered by miniPCR bio. With minor modifications, it could also be used with more advanced students.

3.
CBE Life Sci Educ ; 21(2): ar33, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35471097

RESUMO

The increase in online learning brought on by the COVID-19 pandemic will likely result in a greater availability of online and hybrid course offerings. In this study, students enrolled in parallel sections of a microbiology lab course with in-person labs and either face-to-face (F2F) or all-online lectures (hybrid, H). Course material and method of assessment in the two sections were identical; student demographics were similar. In the first year, F2F students scored significantly higher on two out of four exams. In the second year, two interventions were introduced: team-building activities (in both sections) and online group discussions (H only). Students in both the F2F and H sections reported similar positive teamwork reviews based on Comprehensive Assessment of Team Member Effectiveness (catme.org) and survey data. Although the COVID-19 pandemic eventually forced all learning online, exam scores from the two sections in the first half of the semester were similar, suggesting that the interventions were effective. In both sections, exam scores were positively correlated with entering grade point averages. This study adds to the body of literature supporting the effectiveness of hybrid learning.


Assuntos
COVID-19 , Estudantes , Logro , Humanos , Aprendizagem , Pandemias
4.
Plant Dis ; 96(8): 1104-1110, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30727053

RESUMO

Glyphosate, the active ingredient in Roundup herbicide, inhibits 5-enol-pyruvyl shikimate 3-phophate synthase (EPSPS), an enzyme found in plants, fungi, and bacteria. Plants engineered for glyphosate tolerance with a glyphosate-insensitive EPSPS take up and translocate the herbicide throughout the plant. In greenhouse experiments, we found that application of glyphosate at the recommended field application rate completely controlled alfalfa rust (Uromyces striatus) on 4-week-old plants inoculated with the fungus 3 days after glyphosate treatment. Control was effective in all seven cultivars tested. The level of protection declined with time after application, indicating that control transitory and protection declined with time after inoculation, suggesting that protective treatments have fungistatic activity. Complete control of rust was obtained when glyphosate was applied up to 10 days after inoculation with rust spores, indicating that the herbicide also has curative activity. Treatment increased protection from anthracnose, caused by Colletotrichum trifolii, a hemibiotrophic pathogen, and reduced symptom severity for spring black stem and leaf spot, caused by Phoma medicaginis, a necrotrophic pathogen. These results indicate that glyphosate could be used to help manage foliar diseases in glyphosate-tolerant alfalfa.

5.
Mol Plant Pathol ; 12(8): 786-98, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21726379

RESUMO

Microarray technology was used to identify the genes associated with disease defence responses in the model legume Medicago truncatula. Transcript profiles from M. truncatula cv. Jemalong genotype A17 leaves inoculated with Colletotrichum trifolii and Erysiphe pisi and roots infected with Phytophthora medicaginis were compared to identify the genes expressed in response to all three pathogens and genes unique to an interaction. The A17 genotype is resistant to C. trifolii and E. pisi, exhibiting a hypersensitive response after inoculation, and is moderately susceptible to P. medicaginis. Among the most strongly up-regulated genes in all three interactions were those encoding a hevein-like protein, thaumatin-like protein (TLP) and members of the pathogenesis response (PR)10 family. Transcripts of genes for enzymes in the phenylpropanoid pathway leading to the production of isoflavonoid phytoalexins increased dramatically in response to inoculation with the foliar pathogens. In P. medicaginis-inoculated roots, transcripts of genes in the phenylpropanoid pathway peaked at 5 days post-inoculation, when symptoms became visible. Transcript accumulation of three PR10 family members, a TLP and chalcone synthase (CHS) was assessed in M. truncatula genotype R108 plants. The R108 plants are resistant to C. trifolii and moderately susceptible to E. pisi and P. medicaginis. Transcript accumulation paralleled the stages of pathogen development. To evaluate the role of a TLP, a PR10 family member and CHS in disease resistance, transgenic R108 plants containing interfering RNA (RNAi) constructs were produced. Reduced expression of PR10 and TLP had no effect on the disease phenotype, whereas reduced expression of CHS resulted in increased susceptibility to necrotrophic pathogens.


Assuntos
Medicago truncatula/metabolismo , Medicago truncatula/microbiologia , Aciltransferases/genética , Aciltransferases/metabolismo , Antígenos de Plantas/genética , Antígenos de Plantas/metabolismo , Colletotrichum/patogenicidade , Resistência à Doença/genética , Resistência à Doença/fisiologia , Genótipo , Análise em Microsséries , Fenótipo , Phytophthora/patogenicidade , Doenças das Plantas/microbiologia , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Interferência de RNA
6.
Mol Plant Pathol ; 8(3): 307-19, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-20507501

RESUMO

SUMMARY Powdery mildew is an economically important disease in a number of crop legumes; however, little is known about resistance to the disease in these species. To gain a better understanding of the genetics of resistance and plant responses to powdery mildew in legumes, we developed a pathosystem with Medicago truncatula and Erysiphe pisi. Screening accessions of M. truncatula identified genotypes that are highly susceptible, moderately resistant and highly resistant to the fungus. In the highly resistant genotype, fungal growth was arrested after appressorium development with no colony formation, while in the moderately resistant genotype a small number of colonies formed. Both resistant and moderately resistant genotypes produced hydrogen peroxide and fluorescent compounds at pathogen penetration sites, consistent with a hypersensitive response (HR), although the response was delayed in the moderately resistant genotype. Very little hydrogen peroxide or fluorescence was detected in the susceptible accession. Microarray analysis of E. pisi-induced early transcriptional changes detected 55 genes associated with the basal defence response that were similarly regulated in all three genotypes. These included pathogenesis-related genes and other genes involved in defence, signal transduction, senescence, cell wall metabolism and abiotic stress. Genes associated with the HR response included flavonoid pathway genes, and others involved in transport, transcription regulation and signal transduction. A total of 34 potentially novel unknown genes, including two legume-specific genes, were identified in both the basal response and the HR categories. Potential binding sites for two defence-related transcription regulators, Myb and Whirly, were identified in promoter regions of induced genes, and four novel motifs were found in promoter regions of genes repressed in the resistant interaction.

7.
Genome ; 45(4): 634-45, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12175066

RESUMO

Eight DNA markers spanning an interval of approximately 10 centimorgans (cM) on soybean (Glycine max) molecular linkage group G (MLG-G) were used to identify bacterial artificial chromosome (BAC) clones. Twenty-eight BAC clones in eight distinct contiguous groups (contigs) were isolated from this genome region, along with 59 BAC clones on 17 contigs homoeologous to those on MLG-G. BAC clones in four of the MLG-G contigs were also digested to produce subclones and detailed physical maps. All of the BAC-ends were sequenced, as were the subclones, to estimate proportions in different sequence categories, compare similarities among homoeologs, and explore microsynteny with Arabidopsis. Homoeologous BAC contigs were enriched in repetitive sequences compared with those on MLG-G or the soybean genome as a whole. Fingerprint and cross-hybridization comparisons between MLG-G and homoeologous contigs revealed cases of highly similar physical organization between soybean duplicates, as did DNA sequence comparisons. Twenty-seven out of 78 total sequences on soybean MLG-G showed significant similarity to Arabidopsis. The homologs mapped to six compact genome segments in Arabidopsis, with the longest containing seven homologs spanning two million base pairs. These results extend previous observations of large-scale duplication and selective gene loss in Arabidopsis, suggesting that networks of conserved synteny between Arabidopsis and other angiosperm families can stretch over long physical distances.


Assuntos
Genoma de Planta , Glycine max/genética , Arabidopsis/genética , Cromossomos Artificiais Bacterianos , Duplicação Gênica , Marcadores Genéticos , Dados de Sequência Molecular , Mapeamento Físico do Cromossomo , Sequências Repetitivas de Ácido Nucleico , Análise de Sequência de DNA , Sintenia
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