The type IV filament superfamily (TFF) is a group of
fibrous protein structures that includes a set of cell projections with evolutionarily related
membrane protein
Membrane proteins are common proteins that are part of, or interact with, biological membranes. Membrane proteins fall into several broad categories depending on their location. Integral membrane proteins are a permanent part of a cell membrane ...
s.
The TFF family seems to have originated in the
last universal common ancestor
The last universal common ancestor (LUCA) is the most recent population from which all organisms now living on Earth share common descent—the most recent common ancestor of all current life on Earth. This includes all cellular organisms; t ...
, from where it diversified into
archaella,
type IV pili
A pilus (Latin for 'hair'; plural: ''pili'') is a hair-like appendage found on the surface of many bacteria and archaea. The terms ''pilus'' and '' fimbria'' (Latin for 'fringe'; plural: ''fimbriae'') can be used interchangeably, although some r ...
,
type II secretion system
The type 2 secretion system (often referred to as the type II secretion system or by the initials T2SS) is a type of protein secretion machinery found in various species of Gram-negative bacteria, including many human pathogens such as ''Pseudomo ...
s, and the
Tad pili.
Complexes in the TFF superfamily are unified by the presence of the eponymous type IV
pilin
Pilin refers to a class of fibrous proteins that are found in pilus structures in bacteria. These structures can be used for the exchange of genetic material, or as a cell adhesion mechanism. Although not all bacteria have pili or fimbriae, ba ...
, an
AAA+
AAA, Triple A, or Triple-A is a three-letter initialism or abbreviation which may refer to:
Airports
* Anaa Airport in French Polynesia (IATA airport code AAA)
* Logan County Airport (Illinois) (FAA airport code AAA)
Arts, entertainment, and me ...
ATPase, an integral (cytoplasmic) membrane (IM) platform, and (with the exception of MSH) a
prepilin peptidase
Prepilin peptidase () is an enzyme found in Type IV filament systems responsible for the maturation of the pilin. This enzyme catalyses the following chemical reaction
: Typically cleaves a -Gly-Phe- bond to release an N-terminal, basic peptid ...
.
[
]
References
Bacteriology
Protein complexes
{{Membrane-protein-stub