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Garcia-Soriano, D. A.

Publications and source records attributed to Garcia-Soriano, D. A..

3 recordsLinked to original sources

Pooled optical screening in bacteria using chromosomally expressed barcodes

Optical pooled screening is an important tool to study dynamic phenotypes for libraries of genetically engineered cells. However, the desired engineering often requires that the barcodes used for in situ genotyping are expressed from the chromosome. This has not been possible in bacteria. Here we describe a method for in situ genotyping of libraries with genomic barcodes in Escherichia. coli. The method is applied to measure the intracellular maturation time of 81 red fluorescent proteins.

biophysics↗

ColFeatures: Automated data extraction and classification of bacterial colonies

Examining microbial colonies on agar plates have been at the core of microbiology for many decades. It is usually done manually, and therefore subject to bias besides requiring a considerable amount of time and effort. In order to optimize and standardize the identification of bacterial colonies growing on agar plates, we have developed an open access tool available on GitHub: ColFeatures. The software allows automated identification of bacterial colonies, extracts key morphological data and generate labels that ensure tracking of temporal development. We included machine learning algorithms that provide sorting of environmental isolates by using cluster methodologies. Furthermore, we show how cluster performance is evaluated using index scores (Silhouette, Calinski-Harabasz, Davies-Bouldin) to ensure the outcome of colony classification. As automation becomes more prominent in microbiology, tools as ColFeatures will assist identification of bacterial colonies on agar plates, bypassing human bias and complementing sequencing or mass spectrometry information that often comes attached with a considerable price tag.

microbiology↗

Microfluidic trapping of vesicles reveals membrane-tension dependent FtsZ cytoskeletal re-organisation

The geometry of reaction compartments can affect the outcome of chemical reactions. Synthetic biology commonly uses giant unilamellar vesicles (GUVs) to generate cell-sized, membrane-bound reaction compartments. However, these liposomes are always spherical due to surface area minimization. Here, we have developed a microfluidic chip to trap and reversibly deform GUVs into rod- or cigar-like shapes, including a constriction site in the trap mimicking the membrane furrow in cell division. When we introduce into these GUVs the bacterial tubulin homologue FtsZ, the primary protein of the bacterial Z ring, we find that FtsZ organization changes from dynamic rings to elongated filaments upon GUV deformation, and that these FtsZ filaments align preferentially with the short GUV axis, in particular at the membrane neck. In contrast, pulsing Min oscillations in GUVs remained largely unaffected. We conclude that microfluidic traps are a useful tool for deforming GUVs into non-spherical membrane shapes, akin to those seen in cell division, and for investigating the effect of confinement geometry on biochemical reactions, such as protein filament self-organization.

synthetic biology↗