TCDB is operated by the Saier Lab Bioinformatics Group

9.B.29 The 4-5 TMS Putative Chaparone (4-5PC) Family

The 4-5PC family consists of proteins from Spirochaetes (Leptospira (subfamily 1)) and many potentially distant homologues in other bacteria (subfamilies 2 - 4) as well as archaea (subfamily 5).  They have 200 - 270 aas with 4 - 5 TMSs. Some of them are encoded adjacent to genes coding for membrane fusion proteins (MFPs; 8.A.1) and outer menbrane factors (OMFs; 1.B.17) as well as ABC transporters (Yamada et al. 2012).  They may be important for assembly of multicomponent transporters such as ABC systems (Yamada et al. 2012). These proteins may be distantly related to members of the ABC superfamily (TC# 3.A.1), as well as members of the golgi Yip1 family (TC# 9.B.135) and the UAB5 family (TC# 9.B.333), but these suggestions have not been confirmed. 

This family belongs to the: YIP (YIP) superfamily.

References associated with 9.B.29 family:

Drew, D., D. Sjöstrand, J. Nilsson, T. Urbig, C.N. Chin, J.W. de Gier, and G. von Heijne. (2002). Rapid topology mapping of Escherichia coli inner-membrane proteins by prediction and PhoA/GFP fusion analysis. Proc. Natl. Acad. Sci. USA 99: 2690-2695. 11867724
Yamada, Y., E.B. Tikhonova, and H.I. Zgurskaya. (2012). YknWXYZ is an unusual four-component transporter with a role in protection against sporulation-delaying-protein-induced killing of Bacillus subtilis. J. Bacteriol. 194: 4386-4394. 22707703