1.E.52 The Flp/Fap Pilin Putative Holin (FFPP-Hol) Family The FFPP family is a large diverse family with members from many bacterial phyla. Some members are annotated as Flp or Fap pilin subunits; others are identified as Holin BlyA family members. They have sizes of 50 - 80 aas with a single N-terminal TMS although one member has 99 aas and 2 TMSs. Flp homologues are included in TCDB under TC# 3.A.7.13.1 (pXO1-63) and TC# 3.A.7.15.1 (Flp-1). Their precise functions appear to be unknown.
Examples:
TC#	Name	Organismal Type	Example
1.E.52.1.1	Putative holin, BlyA family	Firmicutes	Putative holin of Ruminococcus obeum

1.E.52.1.2	Uncharacterized protein	Firmicutes	Uncharacterized protein of Ruminococcus bromii

Examples:
TC#	Name	Organismal Type	Example
1.E.52.2.1	Putative holin of 99 aas and 2 TMSs	Actinobacteria	Putative holin of Collinsella intestinalis

Examples:
TC#	Name	Organismal Type	Example
1.E.52.3.1	Putative holin of 54 aas and 1 TMS	Firmicute	Putative holin of Johnsonella ignava

1.E.52.3.2	Flp pilin component	Proteobacteria	Flp pilin compenent of Cupriavidus taiwanensis

1.E.52.3.3	Flp/Fap pilin component	δ-Proteobacteria	Pilin compenent of Anaeromyxobacter dehalogenans

Examples:
TC#	Name	Organismal Type	Example