The sps gene products affect germination, hydrophobicity and protein adsorption of Bacillus subtilis spores

The multilayered surface of the Bacillus subtilis spore is composed of proteins and glycans. While over seventy different proteins have been identified as surface components, carbohydrates associated to the spore surface have not been characterized in details yet. Bioinformatic data suggest that the eleven products of the sps operon are involved in the synthesis of polysaccharides present on the spore surface but an experimental validation is available only for the four distal genes of the operon. Here we report a transcriptional analysis of the sps operon and a functional study performed by constructing and analyzing two null mutants lacking either all or only the promoter proximal gene of the operon. Our results show that both sps mutant spores have apparently normal coat and crust but have a small germination defect and are more hydrophobic than wild type spores. We also show that spores lacking all Sps proteins are highly adhesive and form extensive clumps. In addition, sps mutant spores have an increased efficiency in adsorbing a heterologous enzyme, suggesting the hydrophobic force as a major determinant of spore adsorption and indicating that a deep understanding of the surface properties of the spore is essential for its full development as a surface display platform

A systematic High-Content Screening microscopy approach reveals key roles for Rab33b, OATL1 and Myo6 in nanoparticle trafficking in HeLa cells

Synthetic nanoparticles are promising tools for imaging and drug delivery; however the molecular details of cellular internalization and trafficking await full characterization. Current knowledge suggests that following endocytosis most nanoparticles pass from endosomes to lysosomes. In order to design effective drug delivery strategies that can use the endocytic pathway, or by-pass lysosomal accumulation, a comprehensive understanding of nanoparticle uptake and trafficking mechanisms is therefore fundamental. Here we describe and apply an RNA interference-based high-content screening microscopy strategy to assess the intracellular trafficking of fluorescently-labeled polystyrene nanoparticles in HeLa cells. We screened a total of 408 genes involved in cytoskeleton and membrane function, revealing roles for myosin VI, Rab33b and OATL1 in this process. This work provides the first systematic large-scale quantitative assessment of the proteins responsible for nanoparticle trafficking in cells, paving the way for subsequent genome-wide studies

The archaeology of ancient pastoral sites in the territory of Montescaglioso (4th - 1st century BC). An interdisciplinary approach from the Bradano valley (Basilicata - southern Italy)

This paper discusses a complete set of hoplite armour (panoply), found in tomb 672 at Chiaromonte (Basilicata), consisting of a “Corinthian” helmet, front and back greaves, bronze protection for the left forearm, and an iron sword. The tomb group can be compared to other tombs with panpolies at Chiaromonte, datable to the 6th century BC on the basis of other contexts in the region containing “Corinthian” helmets. Furthermore, the archaeological evidence from Chiaromonte is used to contextualize this important indigenous settlement centre against the backdrop of the “North- Lucanian” and the “Oinotrian” cultures. Finally, 6th-century Chiaromonte is related to the political and military system of Sybaris, mentioned by ancient sources, but so far scarcely attested “on the ground.” The author argues that the elite of Chiaromonte served in the cavalry of Sybaris

The archaeology of ancient pastoral sites in the territory of Montescaglioso (4th - 1st century BC). An interdisciplinary approach from the Bradano valley (Basilicata - southern Italy)

This paper discusses a complete set of hoplite armour (panoply), found in tomb 672 at Chiaromonte (Basilicata), consisting of a \u201cCorinthian\u201d helmet, front and back greaves, bronze protection for the left forearm, and an iron sword. The tomb group can be compared to other tombs with panpolies at Chiaromonte, datable to the 6th century BC on the basis of other contexts in the region containing \u201cCorinthian\u201d helmets. Furthermore, the archaeological evidence from Chiaromonte is used to contextualize this important indigenous settlement centre against the backdrop of the \u201cNorth- Lucanian\u201d and the \u201cOinotrian\u201d cultures. Finally, 6th-century Chiaromonte is related to the political and military system of Sybaris, mentioned by ancient sources, but so far scarcely attested \u201con the ground.\u201d The author argues that the elite of Chiaromonte served in the cavalry of Sybaris

Lysosome triggered near-infrared fluorescence imaging of cellular trafficking processes in real time.

Bioresponsive NIR-fluorophores offer the possibility for continual visualization of dynamic cellular processes with added potential for direct translation to in vivo imaging. Here we show the design, synthesis and lysosome-responsive emission properties of a new NIR fluorophore. The NIR fluorescent probe design differs from typical amine functionalized lysosomotropic stains with off/on fluorescence switching controlled by a reversible phenol/phenolate interconversion. Emission from the probe is shown to be highly selective for the lysosomes in co-imaging experiments using a HeLa cell line expressing the lysosomal-associated membrane protein 1 fused to green fluorescent protein. The responsive probe is capable of real-time continuous imaging of fundamental cellular processes such as endocytosis, lysosomal trafficking and efflux in 3D and 4D. The advantage of the NIR emission allows for direct translation to in vivo tumour imaging, which is successfully demonstrated using an MDA-MB-231 subcutaneous tumour model. This bioresponsive NIR fluorophore offers significant potential for use in live cellular and in vivo imaging, for which currently there is a deficit of suitable molecular fluorescent tools