Protein Family Models

Date:

2024-08-14

This family has been extended to coincide with ref [1]. The KOW (Kyprides, Ouzounis, Woese) motif is found in a variety of ribosomal proteins and NusG. [1]. 8987397. KOW: a novel motif linking a bacterial transcription factor with. ribosomal proteins.. Kyrpides NC, Woese CR, Ouzounis CA;. Trends Biochem Sci 1996;21:425-426. (from Pfam)

Date:

2024-08-14

transcription termination/antitermination protein NusG (N-Utilization Substance G) is involved in transcription elongation and termination in bacteria

Date:

2022-09-13

NusG proteins are transcription factors which are aparrently universal in prokaryotes (archaea and eukaryotes have homologs that may have related functions). The essential components of these factors include an N-terminal RNP-like (ribonucleoprotein) domain and a C-terminal KOW motif (PF00467) believed to be a nucleic acid binding domain [3]. In E. coli, NusA has been shown to interact with RNA polymerase and termination factor Rho. This model covers a wide variety of bacterial species but excludes mycoplasmas which are covered by a separate model (TIGR01956). The function of all of these NusG proteins is likely to be the same at the level of interaction with RNA and other protein factors to affect termination; however different species may utilize NusG towards different processes and in combination with different suites of affector proteins. In E. coli, NusG promotes rho-dependent termination. It is an essential gene. In Streptomyces virginiae and related species, an additional N-terminal sequence is also present and is suggested to play a role in butyrolactone-mediated autoregulation. In Thermotoga maritima, NusG has a long insert, fails to substitute for E. coli NusG (with or without the long insert), is a large 0.7 % of total cellular protein, and has a general, sequence non-specific DNA and RNA binding activity that blocks ethidium staining, yet permits transcription. Archaeal proteins once termed NusG share the KOW domain but are actually a ribosomal protein corresponding to L24p in bacterial and L26e in eukaryotes (TIGR00405).

Gene:

nusG

Date:

2024-06-26