PMID- 35847116
OWN - NLM
STAT- PubMed-not-MEDLINE
LR  - 20220719
IS  - 1664-302X (Print)
IS  - 1664-302X (Electronic)
IS  - 1664-302X (Linking)
VI  - 13
DP  - 2022
TI  - Biomineralization in Cave Bacteria-Popcorn and Soda Straw Crystal Formations, 
      Morphologies, and Potential Metabolic Pathways.
PG  - 933388
LID - 10.3389/fmicb.2022.933388 [doi]
LID - 933388
AB  - Caves are extreme, often oligotrophic, environments that house diverse groups of 
      microorganisms. Many of these microbes can perform microbiologically induced 
      carbonate precipitation (MICP) to form crystalline secondary cave deposits known 
      as speleothems. The urease family is a group of enzymes involved in MICP that 
      catalyze the breakdown of urea, which is a source of energy, into ammonia and 
      carbonate. Carbonate anions are effluxed to the extracellular surface of the 
      bacterium where it then binds to environmental calcium to form calcium carbonate 
      which then continues to grow in crystal form. Here, we studied bacterial 
      communities from speleothems collected from the Iron Curtain Cave (ICC) in 
      Chilliwack, B.C., Canada, to characterize these organisms and determine whether 
      urease-positive (U+) bacteria were present in the cave and their potential impact 
      on speleothem formation. The ICC is a carbonate cave located on the northside of 
      Chipmunk Ridge, presenting a unique environment with high iron content sediment 
      and limestone structures throughout. With six pools of water throughout the cave, 
      the environment is highly humid, with temperatures ranging between 4 and 12 degrees C 
      depending on the time of year. Ninety-nine bacterial strains were isolated from 
      popcorn (PCS) and soda straw (SSS) speleothems. These isolates were screened for 
      urease enzymatic activity, with 11 candidates found to be urease-positive. After 
      incubation, species-specific crystal morphologies were observed. Popcorn 
      speleothem provided more bacterial diversity overall when compared to soda straw 
      speleothem when examined under a culture-based method. Nearly twice as many U+ 
      isolates were isolated from popcorn speleothems compared to soda straw 
      speleothems. The U+ candidates were identified to the genus level by 16S rRNA 
      analysis, and two isolates underwent whole-genome sequencing. Two novel species 
      were identified as Sphingobacterium sp. PCS056 and Pseudarthrobacter sp. SSS035. 
      Both isolates demonstrated the most crystal production as well as the most 
      morphologically dissimilar crystal shapes in broth culture and were found to 
      produce crystals as previously observed in both agar and broth media. The results 
      from this study are consistent with the involvement of urease-positive bacteria 
      isolated from the ICC in the formation of cave speleothems. 16S rRNA sequencing 
      revealed a diverse set of microbes inhabiting the speleothems that have urease 
      activity. Whole-genome sequencing of the two chosen isolates confirmed the 
      presence of urease pathways, while revealing differences in urease pathway 
      structure and number. This research contributes to understanding 
      microbial-associated cave formation and degradation, with applications to cave 
      conservation, microbiota composition, and their role in shaping the cave 
      environment.
CI  - Copyright (c) 2022 Koning, McFarlane, Gosse, Lawrence, Carr, Horne, Van Wagoner, 
      Boddy and Cheeptham.
FAU - Koning, Keegan
AU  - Koning K
AD  - Department of Biology, Faculty of Science, Thompson Rivers University, Kamloops, 
      BC, Canada.
FAU - McFarlane, Richenda
AU  - McFarlane R
AD  - Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, 
      ON, Canada.
FAU - Gosse, Jessica T
AU  - Gosse JT
AD  - Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, 
      ON, Canada.
FAU - Lawrence, Sara
AU  - Lawrence S
AD  - Department of Biology, Faculty of Science, Thompson Rivers University, Kamloops, 
      BC, Canada.
FAU - Carr, Lynnea
AU  - Carr L
AD  - Department of Biology, Faculty of Science, Thompson Rivers University, Kamloops, 
      BC, Canada.
FAU - Horne, Derrick
AU  - Horne D
AD  - The University of British Columbia Bioimaging Facility, Biological Sciences 
      Building, Vancouver, BC, Canada.
FAU - Van Wagoner, Nancy
AU  - Van Wagoner N
AD  - Department of Physical Sciences, Faculty of Science, Thompson Rivers University, 
      Kamloops, BC, Canada.
FAU - Boddy, Christopher N
AU  - Boddy CN
AD  - Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, 
      ON, Canada.
FAU - Cheeptham, Naowarat
AU  - Cheeptham N
AD  - Department of Biology, Faculty of Science, Thompson Rivers University, Kamloops, 
      BC, Canada.
LA  - eng
PT  - Journal Article
DEP - 20220701
PL  - Switzerland
TA  - Front Microbiol
JT  - Frontiers in microbiology
JID - 101548977
PMC - PMC9283089
OTO - NOTNLM
OT  - MICP
OT  - biomineralization
OT  - cave formation
OT  - cave microbiology
OT  - cave microorganisms
OT  - geomicrobiology
OT  - speleothems
OT  - urease
COIS- The authors declare that the research was conducted in the absence of any 
      commercial or financial relationships that could be construed as a potential 
      conflict of interest.
EDAT- 2022/07/19 06:00
MHDA- 2022/07/19 06:01
PMCR- 2022/07/01
CRDT- 2022/07/18 04:11
PHST- 2022/04/30 00:00 [received]
PHST- 2022/05/25 00:00 [accepted]
PHST- 2022/07/18 04:11 [entrez]
PHST- 2022/07/19 06:00 [pubmed]
PHST- 2022/07/19 06:01 [medline]
PHST- 2022/07/01 00:00 [pmc-release]
AID - 10.3389/fmicb.2022.933388 [doi]
PST - epublish
SO  - Front Microbiol. 2022 Jul 1;13:933388. doi: 10.3389/fmicb.2022.933388. 
      eCollection 2022.