scholarly journals Characterization of Unique Regions of Borrelia burgdorferi Surface-Located Membrane Protein 1

2010 ◽  
Vol 78 (11) ◽  
pp. 4477-4487 ◽  
Author(s):  
Xiuli Yang ◽  
Tiffany R. Lenhart ◽  
Toru Kariu ◽  
Juan Anguita ◽  
Darrin R. Akins ◽  
...  

ABSTRACT The pathogen of Lyme disease, Borrelia burgdorferi, produces a putative surface protein termed “surface-located membrane protein 1” (Lmp1). Lmp1 has been shown previously to assist the microbe in evasion of host-acquired immune defenses and in the establishment of persistent infection of mammals. Here, we show that Lmp1 is an integral membrane protein with surface-exposed N-terminal, middle, and C-terminal regions. During murine infection, antibodies recognizing these three protein regions were produced. Separate immunization of mice with each of the discrete regions exerted differential effects on spirochete survival during infection. Notably, antibodies against the C-terminal region primarily interfered with B. burgdorferi persistence in the joints, while antibodies specific to the N-terminal region predominantly affected pathogen levels in the heart, including the development of carditis. Genetic reconstitution of lmp1 deletion mutants with the lmp1 N-terminal region significantly enhanced its ability to resist the bactericidal effects of immune sera and also was observed to increase pathogen survival in vivo. Taken together, the combined data suggest that the N-terminal region of Lmp1 plays a distinct role in spirochete survival and other parts of the protein are related to specific functions corresponding to pathogen persistence and tropism during infection that is displayed in an organ-specific manner. The findings reported here underscore the fact that surface-exposed regions of Lmp1 could potentially serve as vaccine targets or antigenic regions that could alter the course of natural Lyme disease.

2006 ◽  
Vol 74 (12) ◽  
pp. 7024-7028 ◽  
Author(s):  
Evelyn Rossmann ◽  
Veronique Kitiratschky ◽  
Heidelore Hofmann ◽  
Peter Kraiczy ◽  
Markus M. Simon ◽  
...  

ABSTRACT Borrelia burgdorferi complement regulator-acquiring surface protein 1 (CRASP-1), the dominant factor H and FHL-1-binding protein of the Lyme disease spirochete B. burgdorferi, is implicated in pathogen persistence and was recently reported to be nonimmunogenic in humans. Here we show that serum samples from Lyme disease patients contain antibodies with exclusive specificity for nondenatured structural determinants of CRASP-1.


2003 ◽  
Vol 14 (6) ◽  
pp. 2357-2371 ◽  
Author(s):  
Sophie Chantalat ◽  
Rëgis Courbeyrette ◽  
Francesca Senic-Matuglia ◽  
Catherine L. Jackson ◽  
Bruno Goud ◽  
...  

The Sec7 domain guanine nucleotide exchange factors (GEFs) for the GTPase ARF are highly conserved regulators of membrane dynamics and protein trafficking. The interactions of large ARF GEFs with cellular membranes for localization and/or activation are likely to participate in regulated recruitment of ARF and effectors. However, these interactions remain largely unknown. Here we characterize Gmh1p, the first Golgi transmembrane-domain partner of any of the high-molecular-weight ARF-GEFs. Gmh1p is an evolutionarily conserved protein. We demonstrate molecular interaction between the yeast Gmh1p and the large ARF-GEFs Gea1p and Gea2p. This interaction involves a domain of Gea1p and Gea2p that is conserved in the eukaryotic orthologues of the Gea proteins. A single mutation in a conserved amino acid residue of this domain is sufficient to abrogate the interaction, whereas the overexpression of Gmh1p can compensate in vivo defects caused by mutations in this domain. We show that Gmh1p is an integral membrane protein that localizes to the early Golgi in yeast and in human HeLa cells and cycles through the ER. Hence, we propose that Gmh1p acts as a positive Golgi-membrane partner for Gea function. These results are of general interest given the evolutionary conservation of both ARF-GEFs and the Gmh proteins.


2019 ◽  
Vol 93 (3) ◽  
pp. 196-202 ◽  
Author(s):  
Kevin S. Brandt ◽  
Amy J. Ullmann ◽  
Claudia R. Molins ◽  
Kalanthe Horiuchi ◽  
Brad J. Biggerstaff ◽  
...  

2019 ◽  
Author(s):  
Chunxiang Bai ◽  
Hua Yang ◽  
Peng Cui ◽  
Rong Quan ◽  
Ying Zhang

AbstractBorrelia burgdorferi could be occasionally recovered from patients after antibiotic treatment, which indicates it may resist eradication by antibiotic and host defense mechanisms. Skin fibroblast cells have previously been shown to protect the killing of B. burgdorferi by ceftriaxone, a powerful antibiotic commonly used to treat Lyme disease. In this study, we evaluated if fibroblast cells could also protect against the doxycycline+ cefuroxime+ daptomycin drug combination which has previously been shown to completely eradicate highly persistent biofilm-like microcolonies of B. burgdorferi. To do so, we utilized a GFP-labeled B. burgdorferi for infection of murine fibroblast cells and assessed the effect of the drug combination on killing the bacteria in the presence or absence of the fibroblast cells. Surprisingly, we found that fibroblasts could protect B. burgdorferi from being completely killed by the drug combination doxycycline, cefuroxime and daptomycin, which eradicated B. burgdorferi completely in the absence of fibroblast cells. Interestingly, addition of essential oil carvacrol or oregano at 0.1% could enhance the activity of the doxycycline+ cefuroxime+ daptomycin drug combination and led to complete eradication of B. burgdorferi even in the presence of fibroblast cells. Further studies are needed to determine if the essential oil drug combinations could eradicate persistent B. burgdorferi infection in vivo in animal models. Our study provides a useful and convenient ex vivo model for evaluating different drug regimens needed for developing more effective treatment of persistent Lyme disease in the future.


2009 ◽  
Vol 77 (7) ◽  
pp. 2802-2812 ◽  
Author(s):  
Catherine A. Brissette ◽  
Tomasz Bykowski ◽  
Anne E. Cooley ◽  
Amy Bowman ◽  
Brian Stevenson

ABSTRACT Borrelia burgdorferi, the Lyme disease-causing spirochete, can persistently infect its vertebrate hosts for years. B. burgdorferi is often found associated with host connective tissue, where it interacts with components of the extracellular matrix, including fibronectin. Some years ago, a borrelial surface protein, named BBK32, was identified as a fibronectin-binding protein. However, B. burgdorferi BBK32 mutants are still able to bind fibronectin, indicating that the spirochete possesses additional mechanisms for adherence to fibronectin. We now demonstrate that RevA, an unrelated B. burgdorferi outer surface protein, binds mammalian fibronectin in a saturable manner. Site-directed mutagenesis studies identified the amino terminus of the RevA protein as being required for adhesion to fibronectin. RevA bound to the amino-terminal region of fibronectin. RevA binding to fibronectin was not inhibited by salt or heparin, suggesting that adhesin-ligand interactions are primarily nonionic and occur through the non-heparin-binding regions of the fibronectin amino-terminal domains. revA genes are widely distributed among Lyme disease spirochetes, and the present studies determined that all RevA alleles tested bound fibronectin. In addition, RevB, a paralogous protein found in a subset of B. burgdorferi strains, also bound fibronectin. We also confirmed that RevA is produced during mammalian infection but not during colonization of vector ticks and determined that revA transcription is controlled through a mechanism distinct from that of BBK32.


2007 ◽  
Vol 76 (1) ◽  
pp. 391-402 ◽  
Author(s):  
Mahulena Maruskova ◽  
M. Dolores Esteve-Gassent ◽  
Valerie L. Sexton ◽  
J. Seshu

ABSTRACT Borrelia burgdorferi, the causative agent of Lyme disease, undergoes rapid adaptive gene expression in response to environmental signals encountered during different stages of its life cycle in the arthropod vector or the mammalian host. Among all the plasmid-encoded genes of B. burgdorferi, several linear plasmid 54 (lp54)-encoded open reading frames (ORFs) exhibit the greatest differential expression in response to mammalian host-specific temperature, pH, and other uncharacterized signals. These ORFs include members of the paralogous gene family 54 (pgf 54), such as BBA64, BBA65, and BBA66, present on lp54. In an attempt to correlate transcriptional up-regulation of these pgf 54 members to their role in infectivity, we inactivated BBA64 and characterized the phenotype of this mutant both in vitro and in vivo. There were no major differences in the protein profiles between the BBA64 mutant and the control strains, while immunoblot analysis indicated that inactivation of BBA64 resulted in increased levels of BBA65. Moreover, there was no significant difference in the ability of the BBA64 mutant to infect C3H/HeN mice compared to that of its parental or complemented control strains as determined by culturing of viable spirochetes from infected tissues. However, enumeration of spirochetes using quantitative real-time PCR revealed tissue-specific differences, suggesting a minimal role for BBA64 in the survival of B. burgdorferi in select tissues. Infectivity analysis of the BBA64 mutant suggests that B. burgdorferi may utilize multiple determinants to establish infection in mammalian hosts.


2013 ◽  
Vol 20 (6) ◽  
pp. 892-899 ◽  
Author(s):  
Angela M. Floden ◽  
Tammy Gonzalez ◽  
Robert A. Gaultney ◽  
Catherine A. Brissette

ABSTRACTPrevious studies indicated that the Lyme disease spirocheteBorrelia burgdorferiexpresses the RevA outer surface protein during mammalian infection. As an adhesin that promotes bacterial interaction with fibronectin, RevA appears to be a good target for preventive therapies. RevA proteins are highly conserved across all Lyme borreliae, and antibodies against RevA protein are cross-reactive among RevA proteins from diverse strains. Mice infected withB. burgdorferimounted a rapid IgM response to RevA, followed by a strong IgG response that generally remained elevated for more than 12 months, suggesting continued exposure of RevA protein to the immune system. RevA antibodies were bactericidalin vitro. To evaluate the RevA antigen as a potential vaccine, mice were vaccinated with recombinant RevA and challenged withB. burgdorferiby inoculation with a needle or by a tick bite. Cultured tissues from all treatment groups were positive forB. burgdorferi. Vaccinated animals also appeared to have similar levels ofB. burgdorferiDNA compared to nonvaccinated controls. Despite its antigenicity, surface expression, and the production of bactericidal antibodies against it, RevA does not protect againstBorrelia burgdorferiinfection in a mouse model. However, passive immunization with anti-RevA antibodies did prevent infection, suggesting the possible utility of RevA-based immunotherapeutics or vaccine.


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