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Bacterial aggregation assisted by anionic surfactant and calcium ions.
Narendra K Dewangan1, Nhi Tran1, Jing Wang-Reed1
1William A. Brookshire Department of Chemical and Biomolecular Engineering, University of Houston, Houston, TX, 77204-4004, USA. jcconrad@uh.edu.
Soft Matter
|September 29, 2021
Summary
Marine bacteria aggregation is promoted by high concentrations of dioctyl sodium sulfosuccinate (DOSS) surfactant and calcium ions. Proteinase K treatment and bacterial motility also influence this aggregation process.
Area of Science:
- Microbiology
- Biochemistry
Background:
- Surfactants are widely used in various industries, and their interaction with microorganisms can lead to significant changes in microbial behavior.
- Understanding bacterial aggregation is crucial for processes ranging from biofilm formation to environmental remediation.
Purpose of the Study:
- To investigate the key factors influencing the aggregation of marine bacteria in the presence of an anionic surfactant.
- To elucidate the roles of surfactant concentration, calcium ions, proteinaceous components, and motility in bacterial aggregate formation.
Main Methods:
- Utilized absorbance measurements and microscopy to observe and quantify bacterial aggregation.
- Employed proteinase K and DNase1 treatments to assess the involvement of proteins and DNA in aggregate formation.
- Investigated the impact of swimming motility on the aggregation process.
Main Results:
- Marine bacteria Marinobacter hydrocarbonoclasticus SP17 and Halomonas titanicae Bead 10BA formed aggregates in synthetic seawater with dioctyl sodium sulfosuccinate (DOSS).
- Aggregate formation required high DOSS concentrations and calcium ions, but not DOSS micelles.
- Proteinase K, but not DNase1, prevented aggregate formation, indicating a protein-mediated mechanism.
- Swimming motility enhanced bacterial aggregation.
Conclusions:
- Bacterial aggregation in the presence of DOSS is a complex process influenced by multiple factors.
- Proteinaceous substances and calcium ions play critical roles in mediating bacterial aggregation.
- Motility contributes to the formation of bacterial aggregates, suggesting a dynamic interaction between bacterial behavior and environmental conditions.
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