4JK2

X-ray crystal structure of Escherichia coli sigma70 holoenzyme in complex with guanosine pentaphosphate (pppGpp)

4JK2 の概要

• エントリーDOI: 10.2210/pdb4jk2/pdb
• 関連するPDBエントリー: 4IGC 4JK1
• 分子名称: Escherichia coli RNA polymerase alpha subunit, Escherichia coli RNA polymerase beta subunit, Escherichia coli RNA polymerase beta' subunit, ... (7 entities in total)
• 機能のキーワード: transcription, dna, transferase
• 由来する生物種: Escherichia coli; 詳細
• タンパク質・核酸の鎖数: 12
• 化学式量合計: 920758.39

構造登録者

Murakami, K.S. (登録日: 2013-03-09, 公開日: 2013-04-17, 最終更新日: 2023-09-20)

主引用文献

Mechold, U.,Potrykus, K.,Murphy, H.,Murakami, K.S.,Cashel, M.
Differential regulation by ppGpp versus pppGpp in Escherichia coli.
Nucleic Acids Res., 41:6175-6189, 2013

PubMed Abstract: Both ppGpp and pppGpp are thought to function collectively as second messengers for many complex cellular responses to nutritional stress throughout biology. There are few indications that their regulatory effects might be different; however, this question has been largely unexplored for lack of an ability to experimentally manipulate the relative abundance of ppGpp and pppGpp. Here, we achieve preferential accumulation of either ppGpp or pppGpp with Escherichia coli strains through induction of different Streptococcal (p)ppGpp synthetase fragments. In addition, expression of E. coli GppA, a pppGpp 5'-gamma phosphate hydrolase that converts pppGpp to ppGpp, is manipulated to fine tune differential accumulation of ppGpp and pppGpp. In vivo and in vitro experiments show that pppGpp is less potent than ppGpp with respect to regulation of growth rate, RNA/DNA ratios, ribosomal RNA P1 promoter transcription inhibition, threonine operon promoter activation and RpoS induction. To provide further insights into regulation by (p)ppGpp, we have also determined crystal structures of E. coli RNA polymerase-σ(70) holoenzyme with ppGpp and pppGpp. We find that both nucleotides bind to a site at the interface between β' and ω subunits.

PubMed: 23620295
DOI: 10.1093/nar/gkt302

実験手法

X-RAY DIFFRACTION (4.201 Å)