The Alteromonas phage P24 Coat Protein (P24CP) Family  

Coat protein (COP) I and COP II complexes are involved in the transport of proteins between the endoplasmic reticulum and the Golgi apparatus in eukaryotic cells. The formation of COP I/II complexes at membrane surfaces is an early step in vesicle formation and is mastered by p24, a type I transmembrane protein. Oligomerization of p24 monomers may to be mediated and/or stabilized by interactions within the transmembrane domain, and the single p24 TMS appears to selectively bind a single sphingomyelin C18:0 molecule. Pannwitt et al. 2019 showed that sequence-specific dimerization of the p24 TMS is mediated by an LQ7 motif, with Gln(187) being of special importance. Whereas cholesterol has no direct impact on p24 dimerization, binding of a sphingolipid can control dimerization of p24 in rigid membrane regions. The authors suggest that specific binding of a sphingolipid to the p24 transmembrane helix affects p24 dimerization in membranes. A clearly defined p24 dimerization propensity is crucial for p24 activity, which involves shuttling between the endoplasmic reticulum and the Golgi membrane, in which cholesterol and sphingolipid C18:0 concentrations differ (Pannwitt et al. 2019).



Pannwitt, S., M. Stangl, and D. Schneider. (2019). Lipid Binding Controls Dimerization of the Coat Protein p24 Transmembrane Helix. Biophys. J. 117: 1554-1562.


TC#NameOrganismal TypeExample

Coat protein of Alteromonas phage P24 of 195 aas and 1 TMS.  It dimerizes to mediate transport from the ER to the goli apparatus (Pannwitt et al. 2019).

Coat protein of Alteromonas phage P24


Uncharacterized protein of 197 aas.

UP of Paraglaciecola psychrophila


Uncharacterized P22-like coat protein of 201 aas.

UP of uncultured Mediterranean phage uvMED


Uncharacterized protein of 194 aas

UP of Pseudomonas fluorescens


Uncharacterized protein of 203 aas

UP of Vibrio ishigakensis


Uncharacterized protein of 201 aas

UP of Zavarzinella formosa


TC#NameOrganismal TypeExample

AIM24 family protein of 273 aa

AIM24 family protein of Butyricicoccus pullicaecorum


Uncharacterized TIGR00266 family protein of 254 aa

UP of Anaerolineales bacterium


Uncharacterized AIM24 family protein of 231 aa

UP of Methanolobus psychrophilus


Uncharacterized protein of 240 aas

UP of Chlamydomonas reinhardtii


Uncharacterized DUF124 protein of 266 aas

UP of Penicillium brasilianum


Uncharacterized DUF2510 domain-containing protein of 285 aa.

UP of Actinobacterium LLX17