Bacteria use conjugation systems, a subfamily of the type IV secretion to transfer DNA recipient cells. Despite 50 years research, architecture and mechanism action channel mediating across bacterial cell envelope remains obscure. By sensitive, quantifiable assay termed immunoprecipitation (TrIP), we identify contacts between substrate (T-DNA) 6 12 components VirB/D4 system phytopathogen Agrobacterium tumefaciens . Our results define translocation pathway for through machine, specifying...

The Agrobacterium tumefaciens virB gene products are proposed to assemble into a transport system capable of exporting complexes DNA and protein across the bacterial envelope en route plant cells. Nonpolar null mutations were constructed in each 11 genes A. pTiA6NC plasmid. In tumorigenicity assays, delta virB1 mutants exhibited severely attenuated virulence virB2 through virB11 avirulence. NdeI restriction sites introduced at predicted translational start used subclone downstream lacZ or...

Agrobacterium tumefaciens transfers T-DNA into the plant genome by a process mediated Ti plasmid-encoded vir genes. Cleavage at border sequences VirD endonuclease generates linear, single-stranded molecules. In work described in this report, we used electrophoretic mobility shift assays to show that purified virE2 gene product binds DNA. VirE2 protein associates with as shown immunoprecipitation studies VirE2-specific antiserum. The was detected primarily cytoplasm, but also inner and outer...

Bacteria use type IV secretion systems (T4SS) to translocate DNA (T-DNA) and protein substrates across the cell envelope. By transfer immunoprecipitation (TrIP), we recently showed that T-DNA translocates through Agrobacterium tumefaciens VirB/D4 T4SS by forming close contacts sequentially with VirD4 receptor, VirB11 ATPase, inner membrane subunits VirB6 VirB8 and, finally, VirB2 pilin VirB9. Here, TrIP, show nucleoside triphosphate binding site (Walker A motif) mutations do not disrupt...

Journal Article An efficient method for isolation of RNA from tissue cultured plant cells Get access Magid Shirzadegan, Shirzadegan Search other works by this author on: Oxford Academic PubMed Google Scholar Peter Christie, Christie 1Department Biological Sciences, Stanford UniversityStanford, CA 94305, USA Jeffrey R. Seemann Nucleic Acids Research, Volume 19, Issue 21, 11 November 1991, Page 6055, https://doi.org/10.1093/nar/19.21.6055 Published: 1991 history Received: 18 June

Bacterial conjugation systems are members of the large type IV secretion system (T4SS) superfamily. Conjugative transfer F plasmids residing in Enterobacteriaceae was first reported 1940s, yet architecture plasmid-encoded channel and its physical relationship with pilus remain unknown. We visualized F-encoded structures native bacterial cell envelope by situ cryoelectron tomography (CryoET). Remarkably, encode four distinct structures, not just translocation or channel-pilus complex...