OKP beta-lactamase amino-acid variation:                                                   Accession(s) number(s)
OKP enzyme pI (Ref) 3 4 9 10 13 18 19 24 29 30 31 34 43 48 49 50 51 52 55 59 70 86 92 94 129 137 146 181 184 188 192 193 194 197 202 211 229 248 256 263 265 266 267 275 Reference(s) (References)
OKP-A-1 7.8 Y V I S A A V P I T R S V V S G R T A N V Q R R S S A S A K S H T A Q Q E N V P S M A R 1, 2 AM051138 (1), AJ635401* (2)
OKP-A-2 8.0 (1) F Q V A S D T 1, 2 AM051139 (1), AJ635404* (2)
OKP-A-3 7.1 A S A D D T K 1 AM051140, AM051141
OKP-A-4 8.0 F A S D T 1 AM051142
OKP-A-5 7.1 Q L A S R A D D T 1 AM051143
OKP-A-6 8.3 A Q V A S R R A D D T K 1 AM051144
OKP-A-7 7.1 C Q L A S R P A D D A K 1 AM051145, AM051146
OKP-A-8 8.1 V A S D T 1 AM051147
OKP-A-9 7.1 A S A A D D T K 1 AM051148
OKP-A-10 7.1 C P L A S A D D M T K 1 AM051149
OKP-A-11 7.8 A V A S A D T 6 AM850915
OKP-A-12 7.8 A Q V A S A D T 6 AM850916
OKP-A-13 nd I F A S A D 7 FJ534513
OKP-A-14 nd I F A S T D T I 7 FJ534512
OKP-A-15 nd F del del del del del S D T 7 FJ755841
OKP-A-16 nd V A Q V A S A D T 7 FJ755840
OKP-B-1 7.1 (1) Q K I G A M S H T T P S R D D A T G 1, 2 AM051150 (1), AJ635402* (2)
OKP-B-2 7.1 Q K I G A S H T T P S R D D A T G 1 AM051151
OKP-B-3 7.1 Q K I A S H I T T P S R D D A T V G 1 AM051152
OKP-B-4 7.1 Q K I A S H T T P S R D D T V G 1 AM051153, AM051154, AM051155
OKP-B-5 7.1 (3) Q K I A S H T I T T P S R D D T V G 3 AY512506
OKP-B-6 7.1 (3) Q K I A S H T T P S R D D A T G 3 AY850171
OKP-B-7 7.1 Q K I A S H I T T P S R D D A T G 1 AM051156
OKP-B-8 7.1 Q K I A S H T I T T P S R D D A T G 1 AM051157, AM051158
OKP-B-9 7.1 Q K I I A S H T R T P S R D D A T V G 1 AM051159
OKP-B-10 7.1 Q K I A S H T I N T T P S R D D A T V 1 AM051160
OKP-B-11 7.1 T Q K I A T S H I T T P S R D D T V G 1 AM051161
OKP-B-12 6.5 ? ? ? T Q K I G A M S H T T T P S D D A T G 2 AJ635420*
OKP-B-13 nd I Q K I A S H T I T T P S R D D A T V 4 AY825330
OKP-B-14 nd ? ? Q K I A S H T T P S L R D D A T G 5
OKP-B-15 7.3 Q K I A S H T T P S R D D A T V G 6 AM850917
OKP-B-16 7.3 Q K I A S H T I T T P S R D D T G 6 AM850918
OKP-B-17 7.4 Q K I G A S H T T P S R D D T V G 6 AM850919
OKP-B-18 6.8 Q K I G A S H I T T P S D D A T G 6 AM850920
OKP-B-19 7.0 Q K I G A M S H T I T T P S R D D T V G 6 AM850921
OKP-B-20 7.1 Q K I A S H T I T T P S R D D A T V G 6 AM850922
?: Not sequenced (total length = 286 amino-acids)                                                                                    
* partial sequences
del: Deletion
1 - Fevre C., Passet V., Weil F.X., Grimont P.A.D., Brisse S. Unpublished. Variants of the Klebsiella pneumoniae OKP chromosomal beta-lactamase are didivided into two main groups, OKP-A and OKP-B.
2 - Haeggman, S., S. Lofdahl, A. Paauw, J. Verhoef, and S. Brisse. 2004. Diversity and evolution of the class A chromosomal beta-lactamase gene in Klebsiella pneumoniae. Antimicrob Agents Chemother 48:2400-8.
3 - Siebor, E., A. Pechinot, J. M. Duez, and C. Neuwirth. 2005. One new LEN enzyme and two new OKP enzymes in Klebsiella pneumoniae clinical isolates and proposed nomenclature for chromosomal beta-lactamases of this species. Antimicrob Agents Chemother 49:3097-8.
4 - Wang,S.Y., He,L., Zhang,R.Z., Lu,Y.M., Mu,X.K. and Chen,S.W., unpublished
5 - M. Nogueira, submitted (6 amino-acids are not sequenced on each side of the sequence)
6 - Mendonca N, Ferreira E, Canica M. 2009. Genetic diversity of genes encoding OKP and LEN beta-lactamases produced by clinical Klebsiella pneumoniae strains in Portugal. Diagn Microbiol Infect Dis. 63(3):334-8.
7- Likou Zou, Sichuan University,China