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We report the development of a simplified procedure for restriction fragment length polymorphism (RFLP) analysis of mushrooms. We have adapted standard molecular techniques to be amenable to an undergraduate laboratory setting in order to allow students to explore basic questions about fungal diversity and relatedness among mushroom species. The streamlined protocols allowed students to practice important molecular techniques within the context of self-designed investigative projects. This laboratory experience provided opportunities for students to practice strategies for examining molecular diversity among species.Keywords: RFLP analysis, biotechnology education, phylogenetic analysis, mushrooms.Hands-on, investigative laboratories have been widely incorporated as highly successful learning activities in undergraduate molecular biology curricula. In our biotechnology curriculum, we have designed project-based laboratories in which students work collaboratively in international research teams to develop multi-week research projects that provide the context for learning basic molecular technologies. This pedagogical strategy relies on self-motivation to drive student learning and allows students to apply their technical skills toward research questions developed from their own interests. To be successful, the project-based approach requires laboratory methodologies that are dependable, versatile, and easy for students to use. We have developed protocols for molecular phylogenetic analysis that are easily amenable to undergraduate courses in biotechnology or molecular biology. Students learn to apply a standard molecular method toward investigating phylogenetic relationships among fungi by conducting PCR-restriction fragment length polymorphism (RFLP) 1 analysis with commercial mushrooms.

To investigate the input of combined nitrogen by cyanobacteria in mangrove ecosystems and the seasonal fluctuation of this biological process, in situ nitrogen fixation activity was measured in day and night experiments carried out at Maruhubi mangrove ecosystem adjacent to Zanzibar town. Sampling was done for 12 months at two stations: Station I covering sandy sediments and Station II muddy sediments. Associated cyanobacteria genera were identified and environmental variables were measured throughout the study period. A total of 10 genera of cyanobacteria were encountered, two of which were the heterocystous cyanobacteria genera Anabaena and Rivularia and eight the non-heterocystous genera Aphanocapsa, Merismopedia, Lyngbya, Microcoleus, Oscillatoria, Phormidium, Schizothrix and Spirulina. At both stations N 2 fixation during the night was significantly higher (P ≤ 0.05) than during the day. The average N 2 -fixation rates at stations I and II were 1.64 and 1.34 nmole N 2 /hr/m 2 respectively, with no significant differences (P ≤ 0.05) observed between seasons at both stations, or between stations in the rainy season. There was no significant correlation (P ≤ 0.05) between nitrogen fixation and physical-chemical variables, except sediment temperature, which showed a significant direct relationship with N 2 fixation rate at Station I only. The results suggest that in the investigated ecosystem cyanobacterial diversity and nitrogen fixation are high; and generally seasonal changes do not have a significant influence on nitrogen fixation. It is therefore concluded that cyanobacterial diversity and nitrogen fixation process may contribute in the promotion of primary productivity in the mangrove ecosystem adjacent to Zanzibar town.

Bacillus fastidiosus was cultivated in batch and continuous culture on various carbon and nitrogen sources. The enzymes involved in allantoin degradation (allantoinase, urease, carboligase) of B. fastidiosus were hardly affected by either carbon or nitrogen source. In contrast, the enzymes involved in glycerol utilization (glycerol kinase, glycerol 3-phosphate dehydrogenase) were induced during growth on glycerol, but were not affected by the amount of allantoin present.