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* Orn/DAP/Arg decarboxylases family 2 signatures *
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Pyridoxal-dependent decarboxylases  acting  on ornithine, lysine, arginine and
related substrates  can be classified into two different families on the basis
of sequence similarities [1,2]. The second family consists of:

 - Eukaryotic  ornithine decarboxylase (EC 4.1.1.17) (ODC).  ODC catalyzes the
   transformation of ornithine into putrescine.
 - Prokaryotic  diaminopimelic acid decarboxylase (EC 4.1.1.20) (DAPDC). DAPDC
   catalyzes the conversion of diaminopimelic acid into lysine; the last  step
   in the biosynthesis of lysine.
 - Pseudomonas syringae pv. tabaci protein tabA. tabA  is probably involved in
   the biosynthesis of tabtoxin and is highly similar to DAPDC.
 - Bacterial  and  plant  biosynthetic  arginine  decarboxylase  (EC 4.1.1.19)
   (ADC). ADC  catalyzes  the  transformation  of  arginine into agmatine, the
   first step in the biosynthesis of putrescine from arginine.

The above  proteins,  while  most  probably evolutionary related, do not share
extensive regions  of sequence similarities.  We selected two of the conserved
regions as  signature  patterns. The first pattern contains a conserved lysine
residue which is known, in mouse ODC [3], to be the site  of attachment of the
pyridoxal-phosphate group.  The  second  pattern  contains a  stretch of three
consecutive glycine residues and has  been proposed to be part of a substrate-
binding region [4].

-Consensus pattern: [FY]-[PA]-x-K-[SACV]-x(5)-[LIVM]-[LIVMA]-x(2)-[LIVMA]-
                    x(3)-G
                    [K is the pyridoxal-P attachment site]
-Sequences known to belong to this class detected by the pattern: ALL,  except
 for hamster ODC.
-Other sequence(s) detected in SWISS-PROT: NONE.

-Consensus pattern: [LIVMSC]-x(2)-[LIVMF]-[DNS]-[LIVMCA]-G-G-G-[LIVMFY]-
                    x(0,1)-[GSF]
-Sequences known to belong to this class detected by the pattern: ALL.
-Other sequence(s) detected in SWISS-PROT: 6.

-Last update: October 1993 / First entry.

[ 1] Bairoch A.
     Unpublished observations (1993).
[ 2] Martin C., Cami B., Yeh P., Stragier P., Parsot C., Patte J.-C.
     Mol. Biol. Evol. 5:549-559(1988).
[ 3] Poulin R., Lu L., Ackermann B., Bey P., Pegg A.E.
     J. Biol. Chem. 267:150-158(1992).
[ 4] Moore R.C., Boyle S.M.
     J. Bacteriol. 172:4631-4640(1990).