@article{mbs:/content/journal/micro/10.1099/mic.0.2006/004424-0, author = "Riley, Sean P. and Bykowski, Tomasz. and Babb, Kelly and von Lackum, Kate and Stevenson, Brian.", title = "Genetic and physiological characterization of the Borrelia burgdorferi ORF BB0374-pfs-metK-luxS operon", journal= "Microbiology", year = "2007", volume = "153", number = "7", pages = "2304-2311", doi = "https://doi.org/10.1099/mic.0.2006/004424-0", url = "https://www.microbiologyresearch.org/content/journal/micro/10.1099/mic.0.2006/004424-0", publisher = "Microbiology Society", issn = "1465-2080", type = "Journal Article", keywords = "RTase, reverse transcriptase", keywords = "SAM, S-adenosylmethionine", keywords = "AI-2, autoinducer-2", keywords = "Q-RT-PCR, quantitative reverse transcription-PCR", keywords = "DPD, 4,5-dihydroxy-2,3-pentanedione", keywords = "SAH, S-adenosylhomocysteine", keywords = "SRH, S-ribosylhomocysteine", abstract = "The Lyme disease spirochaete, Borrelia burgdorferi, produces the LuxS enzyme both in vivo and in vitro; this enzyme catalyses the synthesis of homocysteine and 4,5-dihydroxy-2,3-pentanedione (DPD) from a by-product of methylation reactions. Unlike most bacteria, B. burgdorferi is unable to utilize homocysteine. However, DPD levels alter expression levels of a subset of B. burgdorferi proteins. The present studies demonstrate that a single B. burgdorferi operon encodes both of the enzymes responsible for synthesis of DPD, as well as the enzyme for production of the Lyme spirochaete's only activated-methyl donor and a probable phosphohydrolase. Evidence was found for only a single transcriptional promoter, located 5′ of the first gene, which uses the housekeeping σ 70 subunit for RNA polymerase holoenzyme function. All four genes are co-expressed, and mRNA levels are growth-rate dependent, being produced during the exponential phase. Thus, high metabolic activity is accompanied by increased cellular levels of the only known borrelial methyl donor, enhanced detoxification of methylation by-products, and increased production of DPD. Therefore, production of DPD is directly correlated with cellular metabolism levels, and may thereby function as an extracellular and/or intracellular signal of bacterial health.", }