Despite the growing importance of agricultural microbiology at the applied, productive and ecological levels, undergraduate degrees in Agronomy generally do not feature much microbiological experimentation. To address this deficiency, we have designed an experimental programme that evaluates the potential of plant growth-promoting rhizobacteria…

In the environment, communication among microorganisms is a key aspect of their lives. Through communication, single cells of a microbial population can coordinate their gene expression and, in consequence, their physiology. Quorum sensing systems (QS) are one of these mechanisms that allow this communication through the production and detection…

Plant extracts and their components have been reported to have antimicrobial properties against phytopathogens. Although such properties could be harnessed for the development of new pathogen control strategies, there are no standardised methods for their assessment in different extracts. The laboratory exercise presented here involves the use of…

"Sinorhizobium meliloti" is a bacterium of great agroeconomic importance because of its ability to fix atmospheric nitrogen in symbiotic association with alfalfa ("Medicago sativa") roots, and it is often used in model studies. We investigated the effects of exopolysaccharides (EPSs) in cell-to-cell and cell-to-surface…

Regulation is a key concept for understanding the dynamics of metabolism in bacteria. This report outlines a simple laboratory experiment aimed at studying a key form of regulation in bacterial metabolism, exemplifying how microbes switch the flux of carbon towards alternative metabolic fates as a function of nutrient availability and according to…

Research and education are two areas often compartmentalised or separated by an abyss, linked in this study by a service-learning methodology, the Small World Initiative project. The programme instruction starts at the university, reaches secondary school and returns to university to complete the research, challenging young students to discover…

Introductory laboratory courses are a standard component of undergraduate science programmes and historically taught using direct instruction/confirmatory lab models. Previous studies have shown that inquiry-based labs enhance student engagement in science courses. However, research on how direct instruction introductory lab courses effectively…

A simple and cheap laboratory class is proposed to illustrate the lethal effect of UV radiation on bacteria and the operation of different DNA repair mechanisms. The class is divided into two sessions, an initial 3-hour experimental session and a second 2-hour analytical session. The experimental session involves two separate experiments: one…

An interdisciplinary and engaging practical is detailed which offers great versatility in the study of a qualitative and quantitative metabolism of azo-dyes by "Staphylococcus aureus". This practical has broad scope for adaptation in the number and depth of variables to allow a focused practical experiment or small research project. Azo-dyes are…

Experimental science activities in primary school enable important cross-curricular learning. In this study, experimental activities on microbiology were carried out by 16 pupils in a Portuguese grade-4 classroom (9-10?years old) and were focused on two problem-questions related to microbiology and health: (1) do your teeth carry microbes? (2) why…

Understanding evolutionary mechanisms is fundamental to a balanced biological education, yet practical demonstrations are rarely considered. In this paper we describe a bacterial liquid microcosm which can be used to demonstrate aspects of evolution, namely adaptive radiation, niche colonisation and competitive fitness. In microcosms inoculated…

The microbial growth curve is widely studied within microbiology classes and bacteria are usually the microbial model used. Here, we describe a novel laboratory protocol involving flow cytometry to assess the growth dynamics of the unicellular microalgae "Isochrysis galbana." The algal model represents an appropriate alternative to…

This paper describes a simple, rapid and low-cost technique for growing bacteria (or other microbes) in an environmental gradient, in order to determine the tolerance of the microbial population to varying concentrations of sodium chloride ions, and suggests how the evolutionary response of a microbial population to the selection pressure of the…

Learning modern genetics is challenging and students have difficulty acquiring a coherent cognitive mental model of abstract concepts such as DNA, bacteria and enzymes. Here we investigated students' mental models of genetics through analysis and interpretation of the discourse that took place while high-school students practised hands-on…

Methods are described for the induction and identification of respiratory deficient mutants in yeast. Practical schemes are given to enable students to obtain dose-response information for physical and chemical mutagens such as heat, ultraviolet light, or acriflavine. A simple test for environmental mutagens is described. (Author/MA)