4itq
From Proteopedia
Crystal structure of hypothetical protein SCO1480 bound to DNA
Structural highlights
FunctionIHF_STRCO A nucleoid-associated protein (NAP) that probably plays a role in chromosome compactation. Contributes to development and secondary metabolism, but is dispensable for growth and viability (PubMed:22038127, PubMed:23427309). Binds to the promoter region of a number of genes (including itself); multiple molecules of the protein bind to the DNA simultaneously, deletion alters the expression of about 30 genes (both up- and down-regulation occurs). Plays a role in controlling viability (PubMed:22038127). Binds dsDNA without any obvious sequence specificity, in a concentration and length-dependent manner. Promotes supercoiling in a topoisomerase-dependent manner (counteracts TopA plasmid relaxation). Binds DNA as a monomer, contacting 8 base pairs via the phosphate backbone; each monomer can bind 2 DNA duplexes, allowing a bridging function (PubMed:23427309). Alters DNA topology, constraining negative supercoils, possibly by DNA twist. Longer dsDNA binds more than one sIHF subunit (PubMed:31376411).[1] [2] [3] Publication Abstract from PubMedEffective chromosome organization is central to the functioning of any cell. In bacteria, this organization is achieved through the concerted activity of multiple nucleoid-associated proteins. These proteins are not, however, universally conserved, and different groups of bacteria have distinct subsets that contribute to chromosome architecture. Here, we describe the characterization of a novel actinobacterial-specific protein in Streptomyces coelicolor. We show that sIHF (SCO1480) associates with the nucleoid and makes important contributions to chromosome condensation and chromosome segregation during Streptomyces sporulation. It also affects antibiotic production, suggesting an additional role in gene regulation. In vitro, sIHF binds DNA in a length-dependent but sequence-independent manner, without any obvious structural preferences. It does, however, impact the activity of topoisomerase, significantly altering DNA topology. The sIHF-DNA co-crystal structure reveals sIHF to be composed of two domains: a long N-terminal helix and a C-terminal helix-two turns-helix domain with two separate DNA interaction sites, suggesting a potential role in bridging DNA molecules. A novel nucleoid-associated protein specific to the actinobacteria.,Swiercz JP, Nanji T, Gloyd M, Guarne A, Elliot MA Nucleic Acids Res. 2013 Feb 20. PMID:23427309[4] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
| ||||||||||||||||||||
Categories: Large Structures | Elliot MA | Gloyd M | Guarne A | Nanji T | Swiercz JP
