Identification of the Novel Leptospiral OmpA-like Protein with ECM and PLG
Binding Properties
Oliveira, R.1,2; Morais, Z.M.3; Gonçales, A.P.3; Romero, E.C.4; Vasconcellos, S.A.3;
Nascimento, A.L.T.O.1,2
1
Centro de Biotecnologia, Instituto Butantan, São Paulo, Brazil; 2Interunidades em
Biotecnologia, ICB, USP, São Paulo, Brazil; 3Laboratório de Zoonoses
Bacterianas do VPS, Faculdade de Medicina Veterinária e Zootecnia, USP, São
Paulo, Brazil; 4Centro de Bacteriologia, Instituto Adolfo Lutz, São Paulo, Brazil
Introduction: Leptospira interrogans is the etiological agent of leptospirosis, a
zoonotic disease of human and veterinary concern. The identification of novel
proteins that mediate host-pathogen interactions is important for understanding the
bacterial pathogenesis as well as to identify protective antigens that would help
fight the disease. Objectives: To study three genes selected from the genome
sequences of Leptospira interrogans serovar Copenhageni and to evaluate the
binding capacity of the recombinant proteins to extracellular matrix (ECM)
components and plasminogen. Methods: The genes LIC10258, LIC12880 and
LIC12238 were cloned in expression vector pAE and inserted in BL21 SI E. coli
strain for proteins expression. The ability of the recombinant proteins to mediate
attachment to ECM components and plasminogen was evaluated by ELISA.
Results: Assessment of the binding capacity of the recombinant proteins with
laminin, collagen type I, collagen type IV, cellular fibronectin and plasma
fibronectin showed that rLIC10258 having the OmpA-like domain binds to laminin
and plasma fibronectin. The binding is dose-dependent and saturable and
therefore it was named Lsa66 (Leptospiral surface adhesin of 66 kDa). No specific
interaction to the ECM components was detected with rLIC12880 e rLIC12238. All
recombinant proteins were capable to bind plasminogen and to generate plasmin,
showing specific proteolytic activity. Conclusions: rLIC10258 is a novel protein
with dual activity that may promote the attachment to host via ECM and may help
the leptospires to overcome tissue barriers by plasmin generation. rLIC10258 is
the first leptospiral OmpA-like protein with ECM and plasminogen binding
properties reported to date.
Supported by: FAPESP, CNPq and Fundação Butantan
Keywords: Leptospira, Leptospirosis, recombinant protein, ECM, plasminogen
���������������������������������������������������������������������������
���������������������������������������������������������������������������������
�����������������������������������������������������