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ABSTRACT Most microorganisms exist in biofilms, which comprise aggregates of cells surrounded by an extracellular matrix that provides protection from external stresses. Based on the conditions under which they form, biofilm structures vary in significant ways. For instance, biofilms that develop when microbes are incubated under static conditions differ from those formed when microbes encounter the shear forces of a flowing liquid. Moreover, biofilms develop dynamically over time. Here, we describe a cost-effective coverslip holder, printed with a three-dimensional (3D) printer, that facilitates surface adhesion assays under a broad range of standing and shaking culture conditions. This m ulti p anel ad hesion (mPAD) mount further allows cultures to be sampled at multiple time points, ensuring consistency and comparability between samples and enabling analyses of the dynamics of biofilm formation. As a proof of principle, using the mPAD mount for shaking, oxic cultures, we confirm previous flow chamber experiments showing that the Pseudomonas aeruginosa wild-type strain and a phenazine deletion mutant (Δ phz ) strain form biofilms with similar structure but reduced density in the mutant strain. Extending this analysis to anoxic conditions, we reveal that microcolony formation and biofilm formation can only be observed under shaking conditions and are decreased in the Δ phz mutant compared to wild-type cultures, indicating that phenazines are crucial for the formation of biofilms if oxygen as an electron acceptor is unavailable. Furthermore, while the model archaeon Haloferax volcanii does not require archaella for surface attachment under static conditions, we demonstrate that an H. volcanii mutant that lacks archaella is impaired in early stages of biofilm formation under shaking conditions. IMPORTANCE Due to the versatility of the mPAD mount, we anticipate that it will aid the analysis of biofilm formation in a broad range of bacteria and archaea. Thereby, it contributes to answering critical biological questions about the regulatory and structural components of biofilm formation and understanding this process in a wide array of environmental, biotechnological, and medical contexts. 

While much research focused on making emphasizes digital and tangible media, few studies have explored making with biology, or biomaking, where people use cells as fabrication units to grow or “make” desired materials for designing real world applications. This lack is especially glaring considering how biomaking and related industries are often aligned with a growing push toward sustainable production as a way of addressing the pressing environmental issues of the day. In order address how maker frameworks could be used as a productive way of bringing biomaking into K-12 contexts, we report on the design and implementation of a biomaking workshop where teams of high school students both assembled a physical biosensor and imagined applications for this technology to address real world issues. Using classroom observations, analysis of classroom projects, and focus group interviews, we examined student experiences and perceptions of these activities in order to ask: What the affordances and challenges of biomaking in supporting maker learning, especially with regard to the less common practices of assembly and imagining? In the discussion, we review what we learned about facilitating biomaking in K-12 setting, as well how our analysis led us to a revaluation of the often crucial but neglected role assembly plays in more ‘typical’ maker activities, and the possibilities for enriching maker activities by including design prototyping and imagination.