Characterization of the Outer Membrane Proteome of Leptospira interrogans Expressed during Acute Lethal Infection

Division of Infectious Diseases, Department of Medicine, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, USA.
Infection and Immunity (Impact Factor: 3.73). 03/2007; 75(2):766-73. DOI: 10.1128/IAI.00741-06
Source: PubMed


Pathogenic Leptospira species adapt to a wide range of environmental conditions during disease transmission and infection. While the proteome of in vitro cultivated Leptospira has been characterized in several studies to date, relatively little is known of the proteome as expressed by Leptospira during disease processes. Isolates of Leptospira obtained from patients suffering the severe pulmonary form of leptospirosis cause acute lethal infection in guinea pigs and chronic asymptomatic infection in rats. Recent studies have demonstrated that protein and lipopolysaccharide constituents of Leptospira recovered from acutely infected guinea pig tissue differ from that of Leptospira in chronically infected rat tissue and in vitro cultivated Leptospira (J. E. Nally, E. Chow, M. C. Fishbein, D. R. Blanco, and M. A. Lovett, Infect. Immun. 73:3251-3260, 2005). In the current study, the proteome of Leptospira expressed during disease processes was characterized relative to that of in vitro cultivated Leptospira (IVCL) after enrichment for hydrophobic membrane proteins with Triton X-114. Protein samples were separated by two-dimensional gel electrophoresis, and antigens expressed during infection were identified by immunoblotting with monospecific antiserum and convalescent rat serum in addition to mass spectrometry. Results suggest a significant increase in the expression of the outer membrane protein Loa22 during acute infection of guinea pigs relative to other outer membrane proteins, whose expression is generally diminished relative to expression in IVCL. Significant amounts of LipL32 are also expressed by Leptospira during acute infection of guinea pigs.

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    • "The proteome of pathogenic leptospires, the causative agent of leptospirosis , expressed during urinary excretion from reservoir hosts of infection, is modulated to facilitate host evasion by diminution of antigen expression and increased expression of the virulence factor Loa22 (Nally et al., 2007; Monahan et al., 2008). Furthermore, proteomic technologies are compatible with novel extraction procedures to enrich for bacterial hydrophobic outer membrane proteins expressed during infection (Nally et al., 2007; Crother and Nally, 2008). Finally, the continued development of novel proteomic approaches such as Capillary Electrophoresis-Mass Spectrometry (CE-MS) have the capability to identify panels of peptides that can be used for disease diagnosis and for differential diagnosis of the causative bacteria of the infections of the mammary gland (Mansor et al., 2013; Albalat et al., 2014). "
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    • "test (such as an ELISA) to replace the MAT and track the epidemiology of the bacteria more accurately. However to date only serovars Copenhageni [11] [12] [13] [14] [15], Pomona [16], and Lai [17] [18] have had their proteomes characterised. In addition improved epidemiology of the bacteria, through the development of a routine protein based ELISA, would enable prophylactic treatment strategies, such as vaccination [19], to be more appropriately implemented for control purposes. "
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    05/2014; 2014:572901. DOI:10.1155/2014/572901
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    • "It is possible that LipL32 function may be affected by posttranslational modification events. The carboxy-terminus of LipL32 undergoes proteolytic cleavage both in vitro [16] and in vivo [47]. Moreover, LipL32 is both phosphorylated and methylated [48], which warrants further studies on this intriguing protein. "
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