SCC transformation requires living donor cells in mixed biofilms.

Methicillin-resistant (MRSA) is an important human pathogen that has emerged through the horizontal acquisition of the staphylococcal cassette chromosome (SCC). Previously, we showed that SCC from heat-killed donors can be transferred via natural transformation in biofilms at frequencies of 10-10. Here, we show an improved transformation assay of SCC with frequencies up to 10 using co-cultured biofilms with living donor cells.

Novel multicellular prokaryote discovered next to an underground stream.

A diversity of prokaryotes currently exhibit multicellularity with different generation mechanisms in a variety of contexts of ecology on Earth. In the present study, we report a new type of multicellular bacterium, HS-3, isolated from an underground stream. HS-3 self-organizes its filamentous cells into a layer-structured colony with the properties of a nematic liquid crystal.

Natural transformation allows transfer of SCCmec-mediated methicillin resistance in Staphylococcus aureus biofilms.

SCCmec is a large mobile genetic element that includes the mecA gene and confers resistance to β-lactam antibiotics in methicillin-resistant Staphylococcus aureus (MRSA). There is evidence that SCCmec disseminates among staphylococci, but the transfer mechanisms are unclear. Here, we show that two-component systems mediate the upregulation of natural competence genes in S.