ABSTRACT This study demonstrates a strict temporal requirement for virulence determinant of the Lyme disease spirochete Borrelia burgdorferi during unique point in its natural infection cycle, which alternates between ticks and small mammals. OspC is major surface protein produced by B. when infected feed but whose synthesis decreases after transmission to mammalian host. We have previously shown that spirochetes lacking are competent replicate migrate salivary glands tick vector do not...

We previously demonstrated that Borrelia burgdorferi requires OspC to colonize a mammalian host. To delineate this requirement, we analyzed the clearance of ospC mutant spirochetes and found they were eliminated within 48 h. conclude B. uses resist innate host defenses immediately after transmission.

Summary Borrelia burgdorferi , the aetiological agent of Lyme disease, follows a life cycle that involves passage between tick vector and mammalian host. To investigate role 36 kb linear plasmid, lp36 (also designated B. K plasmid), in infectious we examined clone lacking this but containing all other plasmids known to be required for infectivity. Our results indicated was not spirochete survival tick, demonstrated low infectivity mammal. Restoration mutant strain confirmed defect due loss...

Complex genetic networks consist of structural modules that determine the levels and timing a cellular response. While functional properties regulatory architectures make up these have been extensively studied, evolutionary history has remained largely unexplored. Here, we investigate transition between direct indirect pathways governing inducible resistance to antibiotic polymyxin B in enteric bacteria. We identify novel architecture -- designated feedforward connector loop relies on...

Borrelia burgdorferi, the bacterial pathogen responsible for Lyme disease, modulates its gene expression profile in response to environments encountered throughout tick-mammal infectious cycle. To begin characterize B. burgdorferi transcriptome during murine infection, we previously employed an vivo technology-based approach (BbIVET). This identified 233 putative promoters, many of which mapped un-annotated regions complex, segmented genome. Herein, globally identify 5' end grown culture as...

Pathogens lacking the enzymatic pathways for de novo purine biosynthesis are required to salvage purines and pyrimidines from host environment synthesis of DNA RNA. Two key enzymes in IMP dehydrogenase (GuaB) GMP synthase (GuaA), encoded by guaB guaA genes, respectively. While these genes typically found on chromosome most bacterial pathogens, guaAB operon Borrelia burgdorferi is present plasmid cp26, which also harbors a number critical B. viability. Using molecular genetics an experimental...

Summary The genome of Borrelia burgdorferi is composed one linear chromosome and approximately 20 circular plasmids. Although some plasmids are required by B. in vivo , most dispensable for growth vitro . However, plasmid (cp) 26 present all natural isolates has never been lost during growth. This carries ospC which critical mammalian infection. We previously showed that cp26 encodes essential functions, including the telomere resolvase, ResT, hence cannot be displaced. Here we identify two...

Metabolic profiling provides a biochemical signature to objectively differentiate two illnesses with nearly identical clinical presentations, early Lyme disease and STARI.

ABSTRACT Borrelia burgdorferi is the tick-borne bacterium that causes multistage inflammatory disease Lyme disease. B. has a reduced genome and lacks enzymes required for de novo synthesis of purines RNA DNA. Therefore, this obligate pathogen dependent upon tick vector mammalian host environments salvage purine bases nucleic acid biosynthesis. This pathway vital survival throughout its infectious cycle, as key in are essential ability spirochete to infect mice critical replication tick. The...

Horizontally acquired genes typically function as autonomous units conferring new abilities when introduced into different species. However, we reasoned that proteins preexisting in an organism might constrain the functionality of a horizontally gene product if it operates on ancestral pathway. Here, determine how pmrD activates PmrA/PmrB two-component system Salmonella enterica but not closely related bacterium Escherichia coli. The PmrD protein binds to phosphorylated PmrA (PmrA-P),...

ABSTRACT Lyme disease is the fastest-growing zoonotic in North America. Current methods for detection of Borrelia burgdorferi infection are challenged by analysis subjectivity and standardization antigen source. In present study, we developed an immuno-PCR (iPCR)-based approach employing recombinant vivo -expressed B. antigens objective a host immune response to infection. iPCR liquid-phase protein method that combines sensitivity PCR with specificity versatility immunoassay-based protocols....

The conversion of nicotinamide to nicotinic acid by nicotinamidase enzymes is a critical step in maintaining NAD(+) homeostasis and contributes numerous important biological processes diverse organisms. In Borrelia burgdorferi, the enzyme, PncA, required for spirochaete survival throughout infectious cycle. Mammals lack nicotinamidases therefore PncA may serve as therapeutic target Lyme disease. Contrary vivo importance current annotation pncA ORF suggests that encoded protein be inactive...

ABSTRACT Borrelia burgdorferi , the causative agent of Lyme disease, has a complex genome consisting linear chromosome and up to 21 circular plasmids. These plasmids encode numerous proteins critical spirochete's infectious cycle many hypothetical whose functions requirements are unknown. The conserved plasmid lp54 encodes several important for survival in mouse-tick cycle, but majority unknown function lack homologs outside borreliae. In this study we adapted Cre- lox recombination system...

Summary Borrelia burgdorferi is an obligate parasite with a limited genome that severely narrows its metabolic and biosynthetic capabilities. Thus survival of this spirochaete in arthropod vector mammalian host requires it can scavenge amino acids, fatty acids nucleosides from blood meal or various tissues. Additionally, the utilization ribonucleotides for DNA synthesis further complicated by lack ribonucleotide reductase conversion nucleoside‐5′‐diphosphates to...

The Lyme disease spirochete Borrelia burgdorferi is dependent on purine salvage from the host environment for survival. genes bbb22 and bbb23 encode permeases that are essential B. mouse infectivity. We now demonstrate unique contributions of each these to transport murine infection. affinities spirochetes carrying alone hypoxanthine adenine were similar those both genes. Spirochetes able achieve wild-type levels saturation but not saturation, suggesting maximal uptake requires presence...

A greater understanding of the molecular mechanisms that Borrelia burgdorferi uses to survive during mammalian infection is critical for development novel diagnostic and therapeutic tools improve clinical management Lyme disease. By use an in vivo expression technology (IVET)-based approach identify B. genes expressed vivo, we discovered bb0318 gene, which thought encode ATPase component a putative riboflavin ABC transport system. Riboflavin metabolite enabling all organisms maintain redox...

Lyme disease is caused by the spirochete Borrelia burgdorferi and transmitted via bite of an infected tick. B. enters skin, disseminates bloodstream, infects various distal tissues, leading to inflammatory sequelae, such as arthritis carditis. linear plasmid 36 (lp36) critical for mammalian infectivity; however, full complement genes on lp36 that contribute this process remains unknown. Through a targeted mutagenesis screen lp36, we identified novel infectivity gene unknown function, bbk13,...

Knowledge of the transcriptional responses vector-borne pathogens at vector-pathogen interface is critical for understanding disease transmission. Borrelia (Borreliella) burgdorferi, causative agent Lyme in United States, transmitted by bite infected Ixodes sp. ticks. It known that B. burgdorferi has altered patterns gene expression during tick acquisition, persistence and Recently, we others have discovered vitro putative non-coding RNAs found internal, overlapping, antisense to annotated...

ABSTRACT A serology-based tiered approach has, to date, provided the most effective means of laboratory confirmation clinically suspected cases Lyme disease, but it lacks sensitivity in early stages disease and is often dependent on subjectively scored immunoblots. We recently demonstrated use immuno-PCR (iPCR) for detecting Borrelia burgdorferi antibodies patient serum samples that were positive disease. To better understand performance iPCR assay, repeatability variability background assay...

Abstract Flagella propel pathogens through their environments, yet are expensive to synthesize and immunogenic. Thus, complex hierarchical regulatory networks control flagellar gene expression. Spirochetes highly motile bacteria, but peculiarly, the archetypal regulator σ 28 is absent in Lyme spirochete Borrelia burgdorferi . Here, we show that bb0268 ( flgV ) B. , previously incorrectly annotated encode RNA-binding protein Hfq, instead a structural component modulates assembly. The broadly...

Regulation of gene expression is critical for the ability Borrelia burgdorferi to adapt different environments during its natural infectious cycle. Reporter genes have been used successfully study regulation in multiple organisms. We introduced a lacZ into B. burgdorferi, and we show that produces protein with detectable β-galactosidase activity both liquid solid media when expressed from constitutive promoter. Furthermore, ospC promoter, detected only clones express ospC, it accurately...