Bisson-Filho, A. | bioRxiv Science

bioRxiv2023

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

Archaea play indispensable roles in global biogeochemical cycles, yet many critical 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 distinct mutants that only form rods or disks. We compared the proteomes of the mutants with wild-type cells across growth phases, thereby distinguishing between protein abundance changes specific to cell shape and those related to growth phases. The corresponding results indicated a diverse set of proteins, including transporters, transducers, signaling components, and transcriptional regulators, as important for cell-shape determination. We also identified structural proteins, including a previously unknown cytoskeletal element, the Hfx. volcanii actin homolog volactin, which plays a role in disk-shape morphogenesis. In summary, we gleaned important insights into archaeal cell-shape determination, with possible implications for understanding the evolution of cell morphology regulation across domains.

microbiology↗

bioRxiv2020

In vivo multi-dimensional information-keeping in Halobacterium salinarum

Shortage of raw materials needed to manufacture components for silicon-based digital memory storage has led to a search for alternatives, including systems for storing texts, images, movies and other forms of information in DNA. Use of DNA as a medium for storage of 3-D information has also been investigated. However, two problems have yet to be addressed: first, storage of 3-D information in DNA has used objects and coding schemes which require large volumes of data; second, the medium used for DNA information-keeping has been inconsistent with qualities needed for long-term data storage. Here, we address these problems. First, we created in vivo DNA-encoded digital archives holding precise specifications for 3- and 4-dimensional figures with unprecedented efficiency. Second, we have demonstrated more robust and longer-lasting information-carriers than earlier repositories for DNA-based data archives by inserting digital information into the halophile, Halobacterium salinarum, an extremophilic archaeon. We then embedded Information-keeping halophiles into crystalline mineral salts in which similar organisms have been shown to persist in stasis for hundreds of millions of years. We propose that digital information archives composed in 3 or more dimensions may be inserted into halophilic organisms and preserved intact for indefinite periods of time.

synthetic biology↗