Protein Family Models

WHH is a predicted nuclease of the HNH/ENDO VII superfamily of the treble clef fold. The name is derived from the conserved motif WHH. It is found in bacterial polymorphic toxin systems [1] and functions as a toxin module. WHH is the shortest version of HNH nuclease families. Like AHH and LHH, the WHH nuclease contains 4 conserved histidines of which the first one is predicted to bind a metal-ion and other three ones are involved in activation of water molecule for hydrolysis [1]. [1]. 21306995. A novel immunity system for bacterial nucleic acid degrading toxins and its recruitment in various eukaryotic and DNA viral systems. Zhang D, Iyer LM, Aravind L;. Nucleic Acids Res. 2011;39:4532-4552. (from Pfam)

Date:

2024-10-16

Colicin-like bacteriocins are complex structures with an N-terminal beta-barrel translocation domain (Pfam:PF09000), a long double-alpha-helical receptor-binding domain (Pfam:PF11570) and this C-terminal RNAse/DNase domain with endonuclease activity. Their competitor bacteriocidal action is by a process that involves binding to a surface receptor, entering the cell, and, finally, killing it. The lethal action of colicin E3 is a specific cleavage in the ribosomal decoding A site. The crystal structure of colicin E3 reveals a Y-shaped molecule with the receptor binding domain forming a 100 Angstrom long stalk and the two globular heads of the translocation domain and this catalytic domain comprising the two arms [2]. [1]. 10368275. The crystal structure of the DNase domain of colicin E7 in complex with its inhibitor Im7 protein. Ko TP, Liao CC, Ku WY, Chak KF, Yuan HS;. Structure. 1999;7:91-102. [2]. 11741540. Crystal structure of colicin E3: implications for cell entry and ribosome inactivation. Soelaiman S, Jakes K, Wu N, Li C, Shoham M;. Mol Cell. 2001;8:1053-1062. (from Pfam)

Date:

2024-10-16

Proteins in this family are involved in the regulation of 1,3-beta-glucan synthase activity and cell-wall formation [1][2]. Genome contextual information showed that SMI1 are primary immunity proteins in bacterial toxin systems [3]. [1]. 7937796. Cloning and characterization of a Neurospora crassa gene required for (1,3) beta-glucan synthase activity and cell wall formation. Enderlin CS, Selitrennikoff CP;. Proc Natl Acad Sci U S A. 1994;91:9500-9504. [2]. 8289782. Cloning and characterization of KNR4, a yeast gene involved in (1,3)-beta-glucan synthesis. Hong Z, Mann P, Brown NH, Tran LE, Shaw KJ, Hare RS, DiDomenico B;. Mol Cell Biol. 1994;14:1017-1025. [3]. 21306995. A novel immunity system for bacterial nucleic acid degrading toxins and its recruitment in various eukaryotic and DNA viral systems. Zhang D, Iyer LM, Aravind L;. Nucleic Acids Res. 2011;39:4532-4552. (from Pfam)

Date:

2024-10-16

SMI1/KNR4 family protein may be involved in the regulation of 1,3-beta-glucan synthase activity and cell-wall formation

Date:

2022-09-01