Ecological role of Acinetobacter calcoaceticus GSN3 in natural biofilm formation and its advantages in bioremediation

Abstract

This study assessed the role of a new Acinetobacter calcoaceticus strain, GSN3, with biofilm-forming and phenol-degrading abilities. Three biofilm reactors were spiked with activated sludge (R1), green fluorescent plasmid (GFP) tagged GSN3 (R2), and their combination (R3). More than 99% phenol removal was achieved during four weeks in R3 while this efficiency was reached after two and four further operational weeks in R2 and R1, respectively. Confocal scanning electron microscopy revealed that GSN3-gfp strains appeared mostly in the deeper layers of the biofilm in R3. After four weeks, almost 7.07 10 7 more attached sludge cells were counted per carrier in R3 in comparison to R1. Additionally, the higher numbers of GSN3-gfp in R2 were unable to increase the efficiency as much as measured in R3. The presence of GSN3-gfp in R3 conveyed advantages, including enhancement of cell immobilization, population diversity, metabolic cooperation and ultimately treatment efficiency.

Beyond Risk: Bacterial Biofilms and Their Regulating Approaches

“…That is, the formation of bacterial biofilms is often important in agricultural and other industrial settings (Bogino et al, 2013;Berlanga and Guerrero, 2016). These beneficial biofilms are currently used as biological control agents against phytopathogens and biofertilizers to enhance crop production (Timmusk et al, 2017), for bioremediation treatment of hazardous pollutants (Irankhah et al, 2019), for wastewater treatment (Ali et al, 2018), for protection of marine ecosystem (Naidoo and Olaniran, 2013), and for prevention of corrosion (Jayaraman et al, 1997;Martinez et al, 2015). Although biofilms can be beneficial to agriculture and industry, people's understanding of the harmfulside of biofilms has been far better than the benefits for decades.…”

Biofilm Formation Reduction by Eugenol and Thymol on Biodegradable Food Packaging Material

“…The European Food Safety Authority (EFSA) recommends these limits [ 8 , 12 ]. In the United States and Canada, the market requires the Food and Drug Administration (FDA) to approve materials and articles for food contact [ 14 ].…”

Correlation Studies of Indigenous Biofilm Forming Bacteria for Resistance Against Selected Metals, Antibiotics and Dyes Degradation

“…Therefore, bacterial communities establish an extracellular polymeric matrix (EPS) that acts as a micro-ecosystem in which different bacteria communicate and interact with each other forming a biofilm. Bacterial biofilm is a complex and highly organized structure consisting of microbial communities living in a self-produced matrix or slime adhered to a biotic or abiotic substratum (Asri et al, 2018;Johanna and Priyanka, 2014;Turki et al, 2017;Irankhah et al 2019). The bacterial species in slime contain structural compounds including proteins, lipids, hydrated biopolymers, carbohydrates and DNA in huge amounts.…”

“…The bacterial species in slime contain structural compounds including proteins, lipids, hydrated biopolymers, carbohydrates and DNA in huge amounts. These microbial communities are diverse in terms of genetic phylogeny (Gbejuade et al, 2015;Mohammed et al, 2013;Sehar and Naz, 2016;Irankhah et al, 2019). The bacterial cells have the ability to adhere to various exteriors e.g.…”

“…Furthermore, it also offers the residing bacteria to adapt to harsh environmental conditions including lack of desired nutrients, temperature and pH fluctuations etc. Biofilm formation is linked to especially horizontal gene transfer as rate of conjugation increases during this process (Fröls et al, 2012;Irankhah et al, 2019;Nisha and Thangavel, 2014;Sehar and Naz, 2016). Now-a-days bacterial biofilms gained a lot of attention because these microbes played a dynamic part in waste water treatment and remediation.…”