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- ****************************************
- * Gas vesicles protein GVPa signatures *
- ****************************************
-
- Gas vesicles are small, hollow, gas filled protein structures found in several
- cyanobacterial and archaebacterial microorganisms [1]. They allow the
- positioning of the bacteria at the favorable depth for growth. Gas vesicles
- are hollow cylindrical tubes, closed by a hollow, conical cap at each end.
- Both the conical end caps and central cylinder are made up of 4-5 nm wide
- ribs that run at right angles to the long axis of the structure. Gas vesicles
- seem to be constituted of two different protein components: GVPa and GVPc.
-
- GVPa, a small protein of about 70 amino acid residues, is the main constituent
- of gas vesicles and form the essential core of the structure. The sequence of
- GVPa is extremely well conserved.
-
- GvpJ and gvpM, two proteins encoded in the cluster of genes required for gas
- vesicle synthesis in the archaebacteria Halobacterium halobium and Haloferax
- mediterranei, have been found [2] to be evolutionary related to GVPa. The
- exact function of these two proteins is not known, although they could be
- important for determining the shape determination gas vesicles.
-
- We developed two signature patterns for this family of proteins. The first
- pattern is located in the N-terminal section while the second is in the C-
- terminal section.
-
- -Consensus pattern: [LIVM]-x-E-[LIVMFYT]-[LIVM]-[DE]-x-[LIVM](2)-[DKR](2)-G-x-
- [LIVM](2)
- -Sequences known to belong to this class detected by the pattern: ALL.
- -Other sequence(s) detected in SWISS-PROT: NONE.
-
- -Consensus pattern: R-[LIVA](3)-A-[GS]-[LIVMFY]-x-T-x(3)-Y-[AG]
- -Sequences known to belong to this class detected by the pattern: ALL.
- -Other sequence(s) detected in SWISS-PROT: NONE.
-
- -Last update: June 1994 / Patterns and text revised.
-
- [ 1] Walsby A.E., Hayes P.K.
- Biochem. J. 264:313-322(1989).
- [ 2] Jones J.G., Young D.C., Dassarma S.
- Gene 102:117-122(1991).
-