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A total of 17 Legionnaires' disease cases were identified in an outbreak in a western town in New York. The cases had symptom onset dates ranging from August 1, 2019, to July 1, 2021. Staff from the New York State Department of Health and Chemung County Health Department employed numerous environmental investigation techniques. Environmental health program staff collected 74 environmental samples, including samples from cooling towers, residences, and a wastewater treatment plant. Wind direction was analyzed to determine the potential for the dispersion of aerosolized Legionella. In total, five cases were found to be genetically related by whole genome sequencing. Further testing revealed that isolates recovered from a cooling tower at an industrial facility were genetically related to four of the 2019 cases. Excessive iron was found in the tower and might have suppressed the oxidizing biocide residual and interfered with the evaluation of routine culture and other testing methods. In 2021, clinical and environmental samples from a private hot tub were found to be genetically related to the four matching cases and cooling tower samples recovered in 2019. Keywords: Legionnaires' disease, Legionella, cooling tower, outbreak, investigation, Introduction Infections from Legionella are a leading cause of waterborne disease outbreaks in the U.S. (Weiss et al., 2017). Legionnaires' disease (LD) is a type of pneumonia caused by inhaling [...]

A total of 17 Legionnaires' disease cases were identified in an outbreak in a western town in New York. The cases had symptom onset dates ranging from August 1, 2019, to July 1, 2021. Staff from the New York State Department of Health and Chemung County Health Department employed numerous environmental investigation techniques. Environmental health program staff collected 74 environmental samples, including samples from cooling towers, residences, and a wastewater treatment plant. Wind direction was analyzed to determine the potential for the dispersion of aerosolized Legionella. In total, five cases were found to be genetically related by whole genome sequencing. Further testing revealed that isolates recovered from a cooling tower at an industrial facility were genetically related to four of the 2019 cases. Excessive iron was found in the tower and might have suppressed the oxidizing biocide residual and interfered with the evaluation of routine culture and other testing methods. In 2021, clinical and environmental samples from a private hot tub were found to be genetically related to the four matching cases and cooling tower samples recovered in 2019. [ABSTRACT FROM AUTHOR]

Many autotrophic microorganisms are likely to adapt to scarcity in dissolved inorganic carbon (DIC; CO2 + HCO3- + CO32-) with CO2 concentrating mechanisms (CCM) that actively transport DIC across the cell membrane to facilitate carbon fixation. Surprisingly, DIC transport has been well studied among cyanobacteria and microalgae only. The deep-sea vent gammaproteobacterial chemolithoautotroph Thiomicrospira crunogena has a low-DIC inducible CCM, though the mechanism for uptake is unclear, as homologs to cyanobacterial transporters are absent. To identify the components of this CCM, proteomes of T. crunogena cultivated under low- and high-DIC conditions were compared. Fourteen proteins, including those comprising carboxysomes, were at least 4-fold more abundant under low-DIC conditions. One of these proteins was encoded by Tcr_0854; strains carrying mutated copies of this gene, as well as the adjacent Tcr_0853, required elevated DIC for growth. Strains carrying mutated copies of Tcr_0853 and Tcr_0854 overexpressed carboxysomes and had diminished ability to accumulate intracellular DIC. Based on reverse transcription (RT)-PCR, Tcr_0853 and Tcr_0854 were cotranscribed and upregulated under low-DIC conditions. The Tcr_0853-encoded protein was predicted to have 13 transmembrane helices. Given the mutant phenotypes described above, Tcr_0853 and Tcr_0854 may encode a two-subunit DIC transporter that belongs to a previously undescribed transporter family, though it is widespread among autotrophs from multiple phyla. [ABSTRACT FROM AUTHOR]

Many autotrophic microorganisms are likely to adapt to scarcity in dissolved inorganic carbon (DIC; CO 2 + HCO 3 - + CO 3 2- ) with CO 2 concentrating mechanisms (CCM) that actively transport DIC across the cell membrane to facilitate carbon fixation. Surprisingly, DIC transport has been well studied among cyanobacteria and microalgae only. The deep-sea vent gammaproteobacterial chemolithoautotroph Thiomicrospira crunogena has a low-DIC inducible CCM, though the mechanism for uptake is unclear, as homologs to cyanobacterial transporters are absent. To identify the components of this CCM, proteomes of T. crunogena cultivated under low- and high-DIC conditions were compared. Fourteen proteins, including those comprising carboxysomes, were at least 4-fold more abundant under low-DIC conditions. One of these proteins was encoded by Tcr_0854 ; strains carrying mutated copies of this gene, as well as the adjacent Tcr_0853 , required elevated DIC for growth. Strains carrying mutated copies of Tcr_0853 and Tcr_0854 overexpressed carboxysomes and had diminished ability to accumulate intracellular DIC. Based on reverse transcription (RT)-PCR, Tcr_0853 and Tcr_0854 were cotranscribed and upregulated under low-DIC conditions. The Tcr_0853 -encoded protein was predicted to have 13 transmembrane helices. Given the mutant phenotypes described above, Tcr_0853 and Tcr_0854 may encode a two-subunit DIC transporter that belongs to a previously undescribed transporter family, though it is widespread among autotrophs from multiple phyla. IMPORTANCE DIC uptake and fixation by autotrophs are the primary input of inorganic carbon into the biosphere. The mechanism for dissolved inorganic carbon uptake has been characterized only for cyanobacteria despite the importance of DIC uptake by autotrophic microorganisms from many phyla among the Bacteria and Archaea In this work, proteins necessary for dissolved inorganic carbon utilization in the deep-sea vent chemolithoautotroph T. crunogena were identified, and two of these may be able to form a novel transporter. Homologs of these proteins are present in 14 phyla in Bacteria and also in one phylum of Archaea , the Euryarchaeota Many organisms carrying these homologs are autotrophs, suggesting a role in facilitating dissolved inorganic carbon uptake and fixation well beyond the genus Thiomicrospira ., (Copyright © 2017 American Society for Microbiology.)