Identification of structural and regulatory cell-shape determinants in Haloferax volcanii.

Archaea play indispensable roles in global biogeochemical cycles, yet many crucial cellular processes, including cell-shape determination, are poorly understood. Haloferax volcanii, a model haloarchaeon, forms rods and disks, depending on growth conditions. Here, we used a combination of iterative proteomics, genetics, and live-cell imaging to identify mutants that only form rods or disks.

Accessible and Insightful Scientific Learning Experiences Using the Microorganism Haloferax volcanii.

Early exposure to science is critical to incite interest in scientific careers, promote equity and retention in STEM fields, and increase the general understanding of the scientific method. For many educators, however, the myriad resources that many scientific experiments require are not readily available. Microbiology experiments in particular can often be inaccessible for a lot of classrooms.

Cost-Effective and Versatile Analysis of Archaeal Surface Adhesion Under Shaking and Standing Conditions.

Biofilms are aggregates of cells surrounded by an extracellular matrix providing protection from external stresses. While biofilms are commonly studied in bacteria, archaea also form such cell aggregates both in liquid cultures and on solid surfaces. Biofilm architectures vary when in liquid cultures versus on surfaces as well as when incubated under static conditions versus under shear forces of flowing liquid.

Immersed Liquid Biofilm and Honeycomb Pattern Formations in Haloferax volcanii.

Biofilms are cellular aggregates encased in extracellular polymeric substances and are commonly formed by single-celled eukaryotes, bacteria, and archaea. In addition to attaching to solid surfaces, these cellular aggregates can also be observed floating on or immersed within liquid cultures. While biofilms on surfaces have been studied in some archaea, little is known about liquid biofilms.

A Twist to the Kirby-Bauer Disk Diffusion Susceptibility Test: an Accessible Laboratory Experiment Comparing Haloferax volcanii and Escherichia coli Antibiotic Susceptibility to Highlight the Unique Cell Biology of Archaea.

Archaea, once thought to only live in extreme environments, are present in many ecosystems, including the human microbiome, and they play important roles ranging from nutrient cycling to bioremediation. Yet this domain is often overlooked in microbiology classes and rarely included in laboratory exercises. Excluding archaea from high school and undergraduate curricula prevents students from learning the uniqueness and importance of this domain.

Advanced Understanding of Prokaryotic Biofilm Formation through Use of a Cost-Effective and Versatile Multipanel Adhesion (mPAD) Mount.

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.

Haloferax volcanii Immersed Liquid Biofilms Develop Independently of Known Biofilm Machineries and Exhibit Rapid Honeycomb Pattern Formation.

The ability to form biofilms is shared by many microorganisms, including archaea. Cells in a biofilm are encased in extracellular polymeric substances that typically include polysaccharides, proteins, and extracellular DNA, conferring protection while providing a structure that allows for optimal nutrient flow. In many bacteria, flagella and evolutionarily conserved type IV pili are required for the formation of biofilms on solid surfaces or floating at the air-liquid interface of liquid media.