LipL32 Is an Extracellular Matrix-Interacting Protein of Leptospira spp. and Pseudoalteromonas tunicata

Abstract

LipL32 is the major outer membrane protein in pathogenic Leptospira. It is highly conserved throughout pathogenic species and is expressed in vivo during human infection. While these data suggest a role in pathogenesis, a function for LipL32 has not been defined. Outer membrane proteins of gram-negative bacteria are the first line of molecular interaction with the host, and many have been shown to bind host extracellular matrix (ECM). A search for leptospiral ECM-interacting proteins identified the major outer membrane protein, LipL32. To verify this finding, recombinant LipL32 was expressed in Escherichia coli and was found to bind Matrigel ECM and individual components of ECM, including laminin, collagen I, and collagen V. Likewise, an orthologous protein found in the genome of Pseudoalteromonas tunicata strain D2 was expressed and found to be functionally similar and immunologically cross-reactive. Lastly, binding activity was mapped to the C-terminal 72 amino acids. These studies show that LipL32 and an orthologous protein in P. tunicata are immunologically cross-reactive and function as ECM-interacting proteins via a conserved C-terminal region.

Calcium Binding to Leptospira Outer Membrane Antigen LipL32 Is Not Necessary for Its Interaction with Plasma Fibronectin, Collagen Type IV, and Plasminogen

“…LipL32 is expressed at high levels on the bacterial surface during both cultivation and natural infection (24). The protein is immunogenic and some studies have implicated LipL32 as an extracellular matrix-binding protein, interacting with collagen type IV, plasma fibronectin, and laminin (11,12). Recently, Vieira et al (13) showed that LipL32 is able to bind to human plasminogen, the inactive precursor of the extracellular proteinase plasmin.…”

“…Studies performed with recombinant LipL32 revealed that this highly immunogenic protein can induce a robust inflammatory response in renal proximal tubule cells (9,10). Furthermore, LipL32 may contribute to host colonization, because it has been demonstrated that it interacts with extracellular matrix (ECM) 3 components, such as collagen type IV, plasma fibronectin, and laminin (11,12) and binds human plasminogen (13).…”

What maintains the high intra-follicular estradiol concentration in pre-ovulatory follicles?

“…This allows for an optimal recovery of these proteins at the purification stage. The following is a sample of papers that used this protocol to recover biotinylated proteins: [7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25]. Following the pre-adsorption phase, the column was then washed with 16 ml of 10 % acetic acid and 0.1 M NaHPO 4 until the pH of the flow-through was >6.8.…”

Avaliação e caracterização de candidatos vacinais voltados para o controle da leptospirose.

“…Apesar disso, a ligação de LipL32 com laminina e colágeno foi demonstrado (HAUK et al, 2008;HOKE et al, 2008). Outra proteína interessante presente na membrana das leptospiras consiste na família de proteínas que apresentam domínios do tipo imunoglobulinas (Ig), nomeadas como LigA, LigB e LigC.…”

“…Várias proteínas de leptospiras com propriedades de ligação específica a laminina e a outros componentes da ECM foram identificadas pelo nosso grupo (ATZINGEN et al, 2008;ATZINGEN et al, 2009;BARBOSA et al, 2006;DOMINGOS et al, 2015;DOMINGOS et al, 2012;FERNANDES et al, 2014;FERNANDES et al, 2012;LONGHI et al, 2009;MENDES et al, 2011;OLIVEIRA et al, 2011;OLIVEIRA et al, 2010; __________________________________________________________Resultados e Discussão 113 2013; SOUZA et al, 2012;VIEIRA et al, 2010b). Outros grupos também identificaram proteínas com capacidade de adesão (CARVALHO et al, 2009;CHOY et al, 2007;HAUK et al, 2008;HOKE et al, 2008;LIN et al, 2009;STEVENSON et al, 2007). De maneira geral, esses dados demonstram o potencial que as leptospiras patogênicas apresentam em aderir nas células do hospedeiro a fim de estabelecer uma infecção.…”