PMID- 36602326
OWN - NLM
STAT- MEDLINE
DCOM- 20230202
LR  - 20230706
IS  - 1098-5336 (Electronic)
IS  - 0099-2240 (Print)
IS  - 0099-2240 (Linking)
VI  - 89
IP  - 1
DP  - 2023 Jan 31
TI  - Convergent Community Assembly among Globally Separated Acidic Cave Biofilms.
PG  - e0157522
LID - 10.1128/aem.01575-22 [doi]
LID - e01575-22
AB  - Acidophilic bacteria and archaea inhabit extreme geochemical "islands" that can 
      tell us when and how geographic barriers affect the biogeography of 
      microorganisms. Here, we describe microbial communities from extremely acidic (pH 
      0 to 1) biofilms, known as snottites, from hydrogen sulfide-rich caves. Given the 
      extreme acidity and subsurface location of these biofilms, and in light of 
      earlier work showing strong geographic patterns among snottite Acidithiobacillus 
      populations, we investigated their structure and diversity in order to understand 
      how geography might impact community assembly. We used 16S rRNA gene cloning and 
      fluorescence in situ hybridization (FISH) to investigate 26 snottite samples from 
      four sulfidic caves in Italy and Mexico. All samples had very low biodiversity 
      and were dominated by sulfur-oxidizing bacteria in the genus Acidithiobacillus. 
      Ferroplasma and other archaea in the Thermoplasmatales ranged from 0 to 50% of 
      total cells, and relatives of the bacterial genera Acidimicrobium and 
      Ferrimicrobium were up to 15% of total cells. Rare phylotypes included 
      Sulfobacillus spp. and members of the phyla "Candidatus Dependentiae" and 
      "Candidatus Saccharibacteria" (formerly TM6 and TM7). Although the same genera of 
      acidophiles occurred in snottites on separate continents, most members of those 
      genera represent substantially divergent populations, with 16S rRNA genes that 
      are only 95 to 98% similar. Our findings are consistent with a model of community 
      assembly where sulfidic caves are stochastically colonized by microorganisms from 
      local sources, which are strongly filtered through environmental selection for 
      extreme acid tolerance, and these different colonization histories are maintained 
      by dispersal restrictions within and among caves. IMPORTANCE Microorganisms that 
      are adapted to extremely acidic conditions, known as extreme acidophiles, are 
      catalysts for rock weathering, metal cycling, and mineral formation in naturally 
      acidic environments. They are also important drivers of large-scale industrial 
      processes such as biomining and contaminant remediation. Understanding the 
      factors that govern their ecology and distribution can help us better predict and 
      utilize their activities in natural and engineered systems. However, extremely 
      acidic habitats are unusual in that they are almost always isolated within 
      circumneutral landscapes. So where did their acid-adapted inhabitants come from, 
      and how do new colonists arrive and become established? In this study, we took 
      advantage of a unique natural experiment in Earth's subsurface to show how 
      isolation may have played a role in the colonization history, community assembly, 
      and diversity of highly acidic microbial biofilms.
FAU - Jones, Daniel S
AU  - Jones DS
AUID- ORCID: 0000-0003-4556-0418
AD  - Earth and Environmental Science, New Mexico Institute of Mining and Technology, 
      Socorro, New Mexico, USA.
AD  - National Cave and Karst Research Institute, Carlsbad, New Mexico, USA.
FAU - Schaperdoth, Irene
AU  - Schaperdoth I
AD  - Department of Geosciences, The Pennsylvania State University, University Park, 
      Pennsylvania, USA.
FAU - Northup, Diana E
AU  - Northup DE
AD  - Department of Biology, University of New Mexico, Albuquerque, New Mexico, USA.
FAU - Gomez-Cruz, Rodolfo
AU  - Gomez-Cruz R
AD  - Biological Sciences Academic Division, Autonomous University Juarez de Tabasco, 
      Villahermosa Centro, Tabasco, Mexico.
FAU - Macalady, Jennifer L
AU  - Macalady JL
AUID- ORCID: 0000-0001-5214-0601
AD  - Department of Geosciences, The Pennsylvania State University, University Park, 
      Pennsylvania, USA.
LA  - eng
PT  - Journal Article
PT  - Research Support, U.S. Gov't, Non-P.H.S.
DEP - 20230105
PL  - United States
TA  - Appl Environ Microbiol
JT  - Applied and environmental microbiology
JID - 7605801
RN  - 0 (RNA, Ribosomal, 16S)
SB  - IM
MH  - RNA, Ribosomal, 16S/genetics
MH  - In Situ Hybridization, Fluorescence
MH  - *Bacteria
MH  - Archaea/genetics
MH  - Biofilms
MH  - *Acidithiobacillus/genetics
MH  - Phylogeny
PMC - PMC9888236
OTO - NOTNLM
OT  - Acidithiobacillus
OT  - acidophiles
OT  - biofilms
OT  - biogeography
OT  - cave
COIS- The authors declare no conflict of interest.
EDAT- 2023/01/06 06:00
MHDA- 2023/02/03 06:00
PMCR- 2023/07/05
CRDT- 2023/01/05 09:03
PHST- 2023/01/06 06:00 [pubmed]
PHST- 2023/02/03 06:00 [medline]
PHST- 2023/01/05 09:03 [entrez]
PHST- 2023/07/05 00:00 [pmc-release]
AID - 01575-22 [pii]
AID - aem.01575-22 [pii]
AID - 10.1128/aem.01575-22 [doi]
PST - ppublish
SO  - Appl Environ Microbiol. 2023 Jan 31;89(1):e0157522. doi: 10.1128/aem.01575-22. 
      Epub 2023 Jan 5.