Regulatory Protein BBD18 of the Lyme Disease Spirochete: Essential Role During Tick Acquisition?

ABSTRACT The Lyme disease spirochete Borrelia burgdorferi senses and responds to environmental cues as it transits between the tick vector and vertebrate host. Failure to properly adapt can block transmission of the spirochete and persistence in either vector or host. We previously identified BBD18,...

Descripción completa

Guardado en:

Detalles Bibliográficos
Autores principales:	Beth M. Hayes, Daniel P. Dulebohn, Amit Sarkar, Kit Tilly, Aaron Bestor, Xavier Ambroggio, Patricia A. Rosa
Formato:	article
Lenguaje:	EN
Publicado:	American Society for Microbiology 2014
Materias:	Microbiology QR1-502
Acceso en línea:	https://doaj.org/article/7d81dad04a714f57a6b5be762eda8e3b
Etiquetas:	Agregar Etiqueta Sin Etiquetas, Sea el primero en etiquetar este registro!

id	oai:doaj.org-article:7d81dad04a714f57a6b5be762eda8e3b
record_format	dspace
spelling	oai:doaj.org-article:7d81dad04a714f57a6b5be762eda8e3b2021-11-15T15:45:12ZRegulatory Protein BBD18 of the Lyme Disease Spirochete: Essential Role During Tick Acquisition?10.1128/mBio.01017-142150-7511https://doaj.org/article/7d81dad04a714f57a6b5be762eda8e3b2014-05-01T00:00:00Zhttps://journals.asm.org/doi/10.1128/mBio.01017-14https://doaj.org/toc/2150-7511ABSTRACT The Lyme disease spirochete Borrelia burgdorferi senses and responds to environmental cues as it transits between the tick vector and vertebrate host. Failure to properly adapt can block transmission of the spirochete and persistence in either vector or host. We previously identified BBD18, a novel plasmid-encoded protein of B. burgdorferi, as a putative repressor of the host-essential factor OspC. In this study, we investigate the in vivo role of BBD18 as a regulatory protein, using an experimental mouse-tick model system that closely resembles the natural infectious cycle of B. burgdorferi. We show that spirochetes that have been engineered to constitutively produce BBD18 can colonize and persist in ticks but do not infect mice when introduced by either tick bite or needle inoculation. Conversely, spirochetes lacking BBD18 can persistently infect mice but are not acquired by feeding ticks. Through site-directed mutagenesis, we have demonstrated that abrogation of spirochete infection in mice by overexpression of BBD18 occurs only with bbd18 alleles that can suppress OspC synthesis. Finally, we demonstrate that BBD18-mediated regulation does not utilize a previously described ospC operator sequence required by B. burgdorferi for persistence in immunocompetent mice. These data lead us to conclude that BBD18 does not represent the putative repressor utilized by B. burgdorferi for the specific downregulation of OspC in the mammalian host. Rather, we suggest that BBD18 exhibits features more consistent with those of a global regulatory protein whose critical role occurs during spirochete acquisition by feeding ticks. IMPORTANCE Lyme disease, caused by Borrelia burgdorferi, is the most common arthropod-borne disease in North America. B. burgdorferi is transmitted to humans and other vertebrate hosts by ticks as they take a blood meal. Transmission between vectors and hosts requires the bacterium to sense changes in the environment and adapt. However, the mechanisms involved in this process are not well understood. By determining how B. burgdorferi cycles between two very different environments, we can potentially establish novel ways to interfere with transmission and limit infection of this vector-borne pathogen. We are studying a regulatory protein called BBD18 that we recently described. We found that too much BBD18 interferes with the spirochete’s ability to establish infection in mice, whereas too little BBD18 appears to prevent colonization in ticks. Our study provides new insight into key elements of the infectious cycle of the Lyme disease spirochete.Beth M. HayesDaniel P. DulebohnAmit SarkarKit TillyAaron BestorXavier AmbroggioPatricia A. RosaAmerican Society for MicrobiologyarticleMicrobiologyQR1-502ENmBio, Vol 5, Iss 2 (2014)
institution	DOAJ
collection	DOAJ
language	EN
topic	Microbiology QR1-502
spellingShingle	Microbiology QR1-502 Beth M. Hayes Daniel P. Dulebohn Amit Sarkar Kit Tilly Aaron Bestor Xavier Ambroggio Patricia A. Rosa Regulatory Protein BBD18 of the Lyme Disease Spirochete: Essential Role During Tick Acquisition?
description	ABSTRACT The Lyme disease spirochete Borrelia burgdorferi senses and responds to environmental cues as it transits between the tick vector and vertebrate host. Failure to properly adapt can block transmission of the spirochete and persistence in either vector or host. We previously identified BBD18, a novel plasmid-encoded protein of B. burgdorferi, as a putative repressor of the host-essential factor OspC. In this study, we investigate the in vivo role of BBD18 as a regulatory protein, using an experimental mouse-tick model system that closely resembles the natural infectious cycle of B. burgdorferi. We show that spirochetes that have been engineered to constitutively produce BBD18 can colonize and persist in ticks but do not infect mice when introduced by either tick bite or needle inoculation. Conversely, spirochetes lacking BBD18 can persistently infect mice but are not acquired by feeding ticks. Through site-directed mutagenesis, we have demonstrated that abrogation of spirochete infection in mice by overexpression of BBD18 occurs only with bbd18 alleles that can suppress OspC synthesis. Finally, we demonstrate that BBD18-mediated regulation does not utilize a previously described ospC operator sequence required by B. burgdorferi for persistence in immunocompetent mice. These data lead us to conclude that BBD18 does not represent the putative repressor utilized by B. burgdorferi for the specific downregulation of OspC in the mammalian host. Rather, we suggest that BBD18 exhibits features more consistent with those of a global regulatory protein whose critical role occurs during spirochete acquisition by feeding ticks. IMPORTANCE Lyme disease, caused by Borrelia burgdorferi, is the most common arthropod-borne disease in North America. B. burgdorferi is transmitted to humans and other vertebrate hosts by ticks as they take a blood meal. Transmission between vectors and hosts requires the bacterium to sense changes in the environment and adapt. However, the mechanisms involved in this process are not well understood. By determining how B. burgdorferi cycles between two very different environments, we can potentially establish novel ways to interfere with transmission and limit infection of this vector-borne pathogen. We are studying a regulatory protein called BBD18 that we recently described. We found that too much BBD18 interferes with the spirochete’s ability to establish infection in mice, whereas too little BBD18 appears to prevent colonization in ticks. Our study provides new insight into key elements of the infectious cycle of the Lyme disease spirochete.
format	article
author	Beth M. Hayes Daniel P. Dulebohn Amit Sarkar Kit Tilly Aaron Bestor Xavier Ambroggio Patricia A. Rosa
author_facet	Beth M. Hayes Daniel P. Dulebohn Amit Sarkar Kit Tilly Aaron Bestor Xavier Ambroggio Patricia A. Rosa
author_sort	Beth M. Hayes
title	Regulatory Protein BBD18 of the Lyme Disease Spirochete: Essential Role During Tick Acquisition?
title_short	Regulatory Protein BBD18 of the Lyme Disease Spirochete: Essential Role During Tick Acquisition?
title_full	Regulatory Protein BBD18 of the Lyme Disease Spirochete: Essential Role During Tick Acquisition?
title_fullStr	Regulatory Protein BBD18 of the Lyme Disease Spirochete: Essential Role During Tick Acquisition?
title_full_unstemmed	Regulatory Protein BBD18 of the Lyme Disease Spirochete: Essential Role During Tick Acquisition?
title_sort	regulatory protein bbd18 of the lyme disease spirochete: essential role during tick acquisition?
publisher	American Society for Microbiology
publishDate	2014
url	https://doaj.org/article/7d81dad04a714f57a6b5be762eda8e3b
work_keys_str_mv	AT bethmhayes regulatoryproteinbbd18ofthelymediseasespirocheteessentialroleduringtickacquisition AT danielpdulebohn regulatoryproteinbbd18ofthelymediseasespirocheteessentialroleduringtickacquisition AT amitsarkar regulatoryproteinbbd18ofthelymediseasespirocheteessentialroleduringtickacquisition AT kittilly regulatoryproteinbbd18ofthelymediseasespirocheteessentialroleduringtickacquisition AT aaronbestor regulatoryproteinbbd18ofthelymediseasespirocheteessentialroleduringtickacquisition AT xavierambroggio regulatoryproteinbbd18ofthelymediseasespirocheteessentialroleduringtickacquisition AT patriciaarosa regulatoryproteinbbd18ofthelymediseasespirocheteessentialroleduringtickacquisition
_version_	1718427594511089664

Regulatory Protein BBD18 of the Lyme Disease Spirochete: Essential Role During Tick Acquisition?

Ejemplares similares