Exploring Miracle Fruit: An Undergraduate Laboratory Exercise on Experimental Design

In recent years, undergraduate biology and biochemistry curricula have seen an increase in the use of course-based undergraduate research experiences (CUREs). CUREs maximize potential student gains when students take an active role in experimental design. Here we propose an activity that can either complement CUREs or function as a stand-alone activity that develops students’ abilities to design an experiment. While most active-learning interventions are designed for the purpose of teaching content, with experimental design skills as a secondary concern, this activity was created primarily to develop experimental design skills, while concurrently teaching important biochemistry concepts. The activity, designed to occur during a single three-hour lab meeting, allows students to experimentally explore the mechanisms of the taste-altering miraculin protein, found in the fruit of Richadella dulcifica, commonly known as miracle fruit. Students in an advanced biology class reported increased understanding of important experimental design concepts and increased knowledge of receptor binding and structural dynamism of proteins. Students also reported learning the importance of identifying nested variables that are difficult to tease apart, particularly when resources, time, or subjects are limited. While intended to develop experimental design skills in an upper-level undergraduate biology course, instructors can adapt the activity to suit biochemistry and introductory biology courses.

Primary image: Miracle Fruit: The image depicts the fruit of Richadella dulcifica, commonly known as Miracle Fruit. This fruit contains the pH-dependent, taste-modifying miraculin protein, which is the subject of this laboratory exercise. https://en.wikipedia.org/wiki/Synsepalum_dulcificum#/media/File:MiracleBerry.jpg (Public Domain)

近年来，大学本科生物学和生物化学课程在课程基础上的本科生研究经验（CUREs）的使用呈现增长趋势。当学生在实验设计方面发挥积极作用时，CUREs可以最大限度地提高学生的潜在收益。在此，我们提出一项活动，该活动既可以作为CUREs的补充，也可以作为一个独立的活动，以培养学生的实验设计能力。虽然大多数主动学习干预措施旨在传授内容知识，将实验设计技能视为次要目标，但本活动的主要目的是发展实验设计技能，同时教授重要的生物化学概念。该活动设计为一堂三小时的实验室会议期间进行，使学生能够实验性地探索奇迹果（Richadella dulcifica）果实中含有的味道改变蛋白质miraculin的机制，奇迹果通常被称为奇迹果。高级生物学课程的学生报告了对重要实验设计概念的深入理解，以及蛋白质受体结合和结构动态性的知识增加。学生们还报告了学习识别嵌套变量的重要性，尤其是当资源、时间或受试者有限时。虽然本活动旨在在高级本科生物学课程中发展实验设计技能，但教师可以根据需要将其调整为生物化学和基础生物学课程。主要图片：奇迹果：该图像展示了Richadella dulcifica（通常称为奇迹果）的果实。这种果实含有pH依赖性的味道改变蛋白miraculin，是该实验室练习的主题。https://en.wikipedia.org/wiki/Synsepalum_dulcificum#/media/File:MiracleBerry.jpg（公有领域）