Chemical signaling in biofilm-mediated biofouling.

Biofouling is the undesirable accumulation of living organisms and their metabolites on submerged surfaces. Biofouling begins with adhesion of biomacromolecules and/or microorganisms and can lead to the subsequent formation of biofilms that are predominantly regulated by chemical signals, such as cyclic dinucleotides and quorum-sensing molecules. Biofilms typically release chemical cues that recruit or repel other invertebrate larvae and algal spores.

improves cold tolerance of Asian rice ( L.) in a genotype-dependent manner by increasing proline in and reduced glutathione in varieties.

Cold stress is an important factor limiting rice production and distribution. Identifying factors that contribute to cold tolerance in rice is of primary importance. While some plant specific genetic factors involved in cold tolerance have been identified, the role of the rice microbiome remains unexplored.

Plant Growth-Promoting Activity of Bacteria Isolated from Asian Rice (Oryza sativa L.) Depends on Rice Genotype.

Asian rice is one of the most important crops because it is a staple food for almost half of the world's population. To have production of rice keep pace with a growing world population, it is anticipated that the use of fertilizers will also need to increase, which may cause environmental damage through runoff impacts. An alternative strategy to increase crop yield is the use of plant growth-promoting bacteria.

Redirecting marine antibiofouling innovations from sustainable horizons.

Biofouling has great environmental, economic, and societal impacts. Emerging and promising strategies for antibiofouling require incorporation of sustainability concepts. To this end, key research priorities should be given to disrupting attachment of organisms or engineering innovative surfaces to slough off fouling organisms from the surfaces, with more holistic considerations of other viable options, including eco-friendly antifouling chemicals.

Dynamic shifts within volatile fatty acid-degrading microbial communities indicate process imbalance in anaerobic digesters.

Buildup of volatile fatty acids (VFAs) in anaerobic digesters (ADs) often results in acidification and process failure. Understanding the dynamics of microbial communities involved in VFA degradation under stable and overload conditions may help optimize anaerobic digestion processes. In this study, five triplicate mesophilic completely mixed AD sets were operated at different organic loading rates (OLRs; 1-6 g chemical oxygen demand [COD] Lday), and changes in the composition and abundance of VFA-degrading microbial communities were monitored using amplicon sequencing and taxon-specific quantitative PCRs, respectively.

A microfluidic platform for the simultaneous quantification of methanogen populations in anaerobic digestion processes.

Methanogens are a diverse group of archaea that play a critical role in the global carbon cycle. The lack of appropriate molecular tools to simultaneously quantify numerous methanogenic taxa, however, has largely limited our ability to study these communities in a wide variety of habitats, such as anaerobic digesters (ADs). In this study, 34 probe-based quantitative PCR (qPCR) assays were designed to target all known methanogenic genera within the archaeal phylum Euryarchaeota.

Quantitative detection of syntrophic fatty acid-degrading bacterial communities in methanogenic environments.

In methanogenic habitats, volatile fatty acids (VFA), such as propionate and butyrate, are major intermediates in organic matter degradation. VFA are further metabolized to H(2), acetate and CO(2) by syntrophic fatty acid-degrading bacteria (SFAB) in association with methanogenic archaea. Despite their indispensable role in VFA degradation, little is known about SFAB abundance and their environmental distribution.

Relating Anaerobic Digestion Microbial Community and Process Function.

Anaerobic digestion (AD) involves a consortium of microorganisms that convert substrates into biogas containing methane for renewable energy. The technology has suffered from the perception of being periodically unstable due to limited understanding of the relationship between microbial community structure and function. The emphasis of this review is to describe microbial communities in digesters and quantitative and qualitative relationships between community structure and digester function.

Methyl coenzyme M reductase (mcrA) gene abundance correlates with activity measurements of methanogenic H₂ /CO₂ -enriched anaerobic biomass.

Biologically produced methane (CH₄) from anaerobic digesters is a renewable alternative to fossil fuels, but digester failure can be a serious problem. Monitoring the microbial community within the digester could provide valuable information about process stability because this technology is dependent upon the metabolic processes of microorganisms. A healthy methanogenic community is critical for digester function and CH₄ production.

Bacterial intracellular sulfur globules: structure and function.

Bacteria that oxidize reduced sulfur compounds like H2S often transiently store sulfur in protein membrane-bounded intracellular sulfur globules; intracellular in this case meaning found inside the cell wall. The cultured bacteria that form these globules are primarily phylogenetically classified in the Proteobacteria and are chemotrophic or photoautotrophic. The current model organism is the purple sulfur bacterium Allochromatium vinosum.

In vitro evaluation of the antimicrobial effect of three endodontic sealers mixed with amoxicillin.

Introduction: The purpose of this in vitro study was to evaluate the antimicrobial effect of mixing amoxicillin with three different sealers when freshly mixed and set.

Methods: Using a direct contact test, Pulp Canal Sealer EWT (SybronEndo Corporation, Orange, CA), AH Plus (Dentsply International Inc, York, PA), and RealSeal SE (Pentron Clinical Technologies LLC, Wallingford, CT) were freshly mixed with amoxicillin and placed on the side wall of the microtiter plate. A 10-microL bacterial suspension of Enterococcus faecalis was placed directly onto the fresh sealers, and sealers set 1 day, 3 days, and 7 days after mixing.

Bioaugmentation for improved recovery of anaerobic digesters after toxicant exposure.

Bioaugmentation was investigated as a method to decrease the recovery period of anaerobic digesters exposed to a transient toxic event. Two sets of laboratory-scale digesters (SRT = 10 days, OLR = 2 g COD/L-day), started with inoculum from a digester stabilizing synthetic municipal wastewater solids (MW) and synthetic industrial wastewater (WW), respectively, were transiently exposed to the model toxicant, oxygen. Bioaugmented digesters received 1.

Dominance of epiphytic filamentous Thiothrix spp. on an aquatic macrophyte in a hydrothermal vent flume in Sedge Bay, Yellowstone Lake, Wyoming.

Sublacustrine hydrothermal vents, geysers, and fumaroles impart regions of Yellowstone Lake with distinctive chemical compositions that generate unique freshwater habitats and support diverse microbial life. Some microbial communities within Sedge Bay manifest themselves as accumulations of white-colored films on the surfaces of aquatic macrophytes located within the hydrothermal flow of vents. It was hypothesized that the white films were the product of microbial growth, particularly sulfur-oxidizing bacteria.

An in vitro comparison of new irrigation and agitation techniques to ultrasonic agitation in removing bacteria from a simulated root canal.

Introduction: This in vitro study compared 3 agitation and 2 irrigation devices to ultrasonic agitation at mechanically removing bacteria from a plastic simulated canal, instrumented to 35/.06.

Methods: The plastic blocks were divided into seven groups.

Can jua be a weapon in combating oral diseases?

Jua (or Joazeiro) is a plant that has been used in Brazil as a folk remedy for many diseases, but mostly as a dentifrice. Several scientific investigations have been conducted in Brazil to examine the therapeutic use of Jua for oral health. This article presents information about the Ziziphus joazeiro plant, its medicinal use, and its chemical components while also reviewing the literature concerning Jua and especially its anti-plaque activity.

An in vitro comparison of bacterial leakage of three common restorative materials used as an intracoronal barrier.

The purpose of this in vitro study was to evaluate quantitatively the effectiveness of three different restorative materials used as an intracoronal barrier to prevent microleakage of endodontically treated teeth. Fifty-five extracted human single-canal teeth were used in this study. The teeth were endodontically prepared and obturated.

An in vitro comparison of the antimicrobial effects of various endodontic medicaments on Enterococcus faecalis.

The purpose of this in vitro study was to investigate the antimicrobial action of Dermacyn (Oculus Innovative Sciences, Petaluma, CA), BioPure MTAD (Dentsply Tulsa Dental, Johnson City, TN), 2% chlorhexidine (CHX; Ultradent, West Jordan, UT), and 5.25% sodium hypochlorite (NaOCl) against Enterococcus faecalis (American Type Culture Collection 4082). Eighteen Petri dishes of BHI agar were inoculated with E faecalis.

In vitro evaluation of the antimicrobial effects of a root canal sealer-antibiotic combination against Enterococcus faecalis.

The purpose of this in vitro study was to evaluate the antimicrobial effects of five antibiotics when added to Kerr Pulp Canal Sealer EWT against Enterococcus faecalis. Five antibiotics: amoxicillin, penicillin, clindamycin, metronidazole, and doxycycline, were added separately to Kerr sealer. Thirty brain heart infusion agar plates were inoculated with E.

The effects of natural biofilms on the reattachment of young adult zebra mussels to artificial substrata.

This laboratory study examined the effects of natural biofilms on the reattachment of young adult zebra mussels, Dreissena polymorpha, in Petri dishes. Natural biofilms were developed in glass and polystyrene Petri dishes using water samples collected at various times of the year. Biofilms were developed over 1, 3, 8, and 14 d.