Dataset Information

Bubble biofilm: Bacterial colonization of air-air interface.

ABSTRACT: Microbial mats or biofilms are known to colonize a wide range of substrates in aquatic environments. These dense benthic communities efficiently recycle nutrients and often exhibit high tolerance to environmental stressors, characteristics that enable them to inhabit harsh ecological niches. In some special cases, floating biofilms form at the air-water interface residing on top of a hydrophobic microlayer. Here, we describe biofilms that reside at the air-air interface by forming gas bubbles (bubble biofilms) in the former Ytterby mine, Sweden. The bubbles are built by micrometer thick membrane-like biofilm that holds enough water to sustain microbial activity. Molecular identification shows that the biofilm communities are dominated by the neuston bacterium Nevskia. Gas bubbles contain mostly air with a slightly elevated concentration of carbon dioxide. Biofilm formation and development was monitored in situ using a time-lapse camera over one year, taking one image every second hour. The bubbles were stable over long periods of time (weeks, even months) and gas build-up occurred in pulses as if the bedrock suddenly exhaled. The result was however not a passive inflation of a dying biofilm becoming more fragile with time (as a result of overstretching of the organic material). To the contrary, microbial growth lead to a more robust, hydrophobic bubble biofilm that kept the bubbles inflated for extended periods (several weeks, and in some cases even months).

SUBMITTER: Sjoberg S

PROVIDER: S-EPMC7798470 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Similar Datasets

Project description:In aquatic environments, Caulobacter spp. can be found at the boundary between liquid and air known as the neuston. I report an approach to study temporal features of Caulobacter crescentus colonization and pellicle biofilm development at the air-liquid interface and have defined the role of cell surface structures in this process. At this interface, C. crescentus initially forms a monolayer of cells bearing a surface adhesin known as the holdfast. When excised from the liquid surface, this monolayer strongly adheres to glass. The monolayer subsequently develops into a three-dimensional structure that is highly enriched in clusters of stalked cells known as rosettes. As this pellicle film matures, it becomes more cohesive and less adherent to a glass surface. A mutant strain lacking a flagellum does not efficiently reach the surface, and strains lacking type IV pili exhibit defects in organization of the three-dimensional pellicle. Strains unable to synthesize the holdfast fail to accumulate at the boundary between air and liquid and do not form a pellicle. Phase-contrast images support a model whereby the holdfast functions to trap C. crescentus cells at the air-liquid boundary. Unlike the holdfast, neither the flagellum nor type IV pili are required for C. crescentus to partition to the air-liquid interface. While it is well established that the holdfast enables adherence to solid surfaces, this study provides evidence that the holdfast has physicochemical properties that allow partitioning of nonmotile mother cells to the air-liquid interface and facilitate colonization of this microenvironment.IMPORTANCE In aquatic environments, the boundary at the air interface is often highly enriched with nutrients and oxygen. Colonization of this niche likely confers a significant fitness advantage in many cases. This study provides evidence that the cell surface adhesin known as a holdfast enables Caulobacter crescentus to partition to and colonize the air-liquid interface. Additional surface structures, including the flagellum and type IV pili, are important determinants of colonization and biofilm formation at this boundary. Considering that holdfast-like adhesins are broadly conserved in Caulobacter spp. and other members of the diverse class Alphaproteobacteria, these surface structures may function broadly to facilitate colonization of air-liquid boundaries in a range of ecological contexts, including freshwater, marine, and soil ecosystems.

Project description:PurposeTo compare the efficacy of air bubble tamponade alone versus air bubble tamponade with internal fluid aspiration for nonplanar Descemet's membrane detachment after clear corneal incision phacoemulsification.MethodsThis study is a prospective, intervention, comparative randomised clinical trial, conducted at a private eye centre, Ismailia, Egypt, from March 2019 to March 2020. It contained 30 eyes of 24 patients who had postphacoemulsification nonplanar Descemet's membrane detachment involving the periphery and the central area of the cornea (>50% of the cornea) with corneal oedema. The patients were divided into two groups: group A: patients with nonplanar DMD affecting the central cornea treated by air bubble tamponade only and group B: patients with nonplanar DMD affecting the central cornea treated by air bubble tamponade augmented by internal fluid aspiration. Trial Registration: This trial was registered at www.pactr.org and the identification number for the registry is PACTR202006612296119.ResultsDuring the 12-month study period, this study included 30 eyes (24 patients) out of 1356 phaco surgeries with postphacoemulsification nonplanar Descemet's membrane detachment. Six patients had DMD in both eyes, eight patients had DMD in the right eye, and ten patients had DMD in the left eye. All patients have successful surgeries without complications. The calculated incidence rate for visually significant DMD was 2.2% per year. The mean ± SD time interval from cataract surgery to the primary intervention was 4.2 ± 1.1 days. Descemet's membrane was attached in 56.25% of patients in group A (9 out of 16 eyes) and 92.6% of patients in group B (13 out of 14 eyes) with a minimum of one-month follow-up.ConclusionAir descemetopexy combined with the internal fluid aspiration demonstrated to be more efficient than air descemetopexy only to treat Descemet's membrane detachment following phacoemulsification. It should be tried before planning other major surgeries in patients with severe Descemet's membrane detachment.

Dataset Information

Bubble biofilm: Bacterial colonization of air-air interface.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets