Laboratory growth of denitrifying water column microbial consortia from deep-sea shipwrecks in the northern Gulf of Mexico.

: Shipwrecks serve as a rich source for novel microbial populations that have largely remained undiscovered. Low temperatures, lack of sunlight, and the availability of substrates derived from the shipwreck's hull and cargo may provide an environment in which microbes can develop unique metabolic adaptations.   : To test our hypothesis that shipwrecks could influence the microbial population involved in denitrification when a consortium is grown in the laboratory, we collected samples proximate to two steel shipwrecks in the northern Gulf of Mexico.

Controlling autonomous underwater floating platforms using bacterial fermentation.

Biogenic gas has a wide range of energy applications from being used as a source for crude bio-oil components to direct ignition for heating. The current study describes the use of biogenic gases from Clostridium acetobutylicum for a new application-renewable ballast regeneration for autonomous underwater devices. Uninterrupted (continuous) and blocked flow (pressurization) experiments were performed to determine the overall biogas composition and total volume generated from a semirigid gelatinous matrix.

Enhancing the fouling resistance of biocidal urethane coatings via surface chemistry modulation.

A group of novel cross-linked polyurethane materials with varying ratios of hydroxyl-terminated macrodiols and tethered quaternary ammonium biocides have been prepared. The resulting materials had a wide range of thermal, mechanical, and surface properties, dictated by the macrodiol composition and biocide concentration. The complex interplay between surface chemistry and biocide concentration was shown to have a profound effect on the fouling resistance of these materials.

Coatings capable of germinating and neutralizing Bacillus anthracis endospores.

Endospores are formed by various bacterial families, including Bacillus and Clostridium, in response to environmental stresses as a means to survive conditions inhospitable to vegetative growth. Although metabolically inert, the endospore must interact with its environment to determine an optimal time to return to a vegetative state, a process known as germination. Germination has been shown to occur in response to a variety of chemical stimuli from specific nutrient germinants including amino acids, sugars and nucleosides.

Biodegradation of medium chain hydrocarbons by Acinetobacter venetianus 2AW immobilized to hair-based adsorbent mats.

The natural attenuation of hydrocarbons can be hindered by their rapid dispersion in the environment and limited contact with bacteria capable of oxidizing hydrocarbons. A functionalized composite material is described herein, that combines in situ immobilized alkane-degrading bacteria with an adsorbent material that collects hydrocarbon substrates, and facilitates biodegradation by the immobilized bacterial population. Acinetobacter venetianus 2AW was isolated for its ability to utilize hydrophobic n-alkanes (C10-C18) as the sole carbon and energy source.

Development of broad-spectrum antimicrobial latex paint surfaces employing active amphiphilic compounds.

With the increase in antibiotic-resistant microbes, the production of self-decontaminating surfaces has become an area of research that has seen a surge of interest in recent years. Such surfaces, when incorporated into commercial products such as children's toys, medical devices and hospital surfaces could reduce the number of infections caused by pathogenic microorganisms. A number of active components for self-decontaminating surfaces have been investigated, including common antibiotics, metal ions, quaternary ammonium salts (QAS), and antimicrobial peptides (AMP).

Synthesis and development of a multifunctional self-decontaminating polyurethane coating.

A unique, durable, nonleaching antimicrobial urethane coating possessing energy-dampening properties is reported. Five novel diol-functionalized quaternary ammonium bromide salts were designed, synthesized, and cross-linked with a commercial polyisocyanate to afford novel multifunctional self-decontaminating coatings. Leaching of the antimicrobial into the environment is eliminated because of the biocidal tether.

Development of antimicrobial peptides (AMPs) for use in self-decontaminating coatings.

Antimicrobial peptides (AMPs) are a class of short polypeptides usually associated with the host organism's innate immune system. AMPs have been identified in a wide range of host organisms, including plants, amphibians, fish, and humans. These peptides usually consist of 30-100 amino acids and are most often cationic.

Evidence for singlet-oxygen generation and biocidal activity in photoresponsive metallic nitride fullerene-polymer adhesive films.

The adhesive properties, as measured by bulk tack analysis, are found to decrease in blends of isomerically pure Sc3N@I(h)-C80 metallic nitride fullerene (MNF) and polystyrene-block-polyisoprene-block-polystyrene (SIS) copolymer pressure-sensitive adhesive under white light irradiation in air. The reduction of tack is attributed to the in situ generation of 1O2 and subsequent photooxidative cross-linking of the adhesive film. Comparisons are drawn to classical fullerenes C60 and C70 for this process.

Surface self-concentrating amphiphilic quaternary ammonium biocides as coating additives.

A variety of amphiphilic quaternary dimethylammonium compounds bearing n-alkyl and oxyethylene groups have been designed and synthesized as antimicrobial additives for use in self-decontaminating surfaces. The effectiveness of these additives stems from a unique ability to self-concentrate at the air-polymer interface without the incorporation of exotic perfluorinated or polymeric functionalities. X-ray photoelectron spectroscopy analysis reveals surface enrichment as high as 18-fold, providing a 7-log reduction of both Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria.

The herpes simplex virus UL20 protein functions in glycoprotein K (gK) intracellular transport and virus-induced cell fusion are independent of UL20 functions in cytoplasmic virion envelopment.

The HSV-1 UL20 protein (UL20p) and glycoprotein K (gK) are both important determinants of cytoplasmic virion morphogenesis and virus-induced cell fusion. In this manuscript, we examined the effect of UL20 mutations on the coordinate transport and Trans Golgi Network (TGN) localization of UL20p and gK, virus-induced cell fusion and infectious virus production. Deletion of 18 amino acids from the UL20p carboxyl terminus (UL20 mutant 204t) inhibited intracellular transport and cell-surface expression of both gK and UL20, resulting in accumulation of UL20p and gK in the endoplasmic reticulum (ER) in agreement with the inability of 204t to complement UL20-null virus replication and virus-induced cell fusion.

UL20 protein functions precede and are required for the UL11 functions of herpes simplex virus type 1 cytoplasmic virion envelopment.

Egress of herpes simplex virus type 1 (HSV-1) from the nucleus of the infected cell to extracellular spaces involves a number of distinct steps, including primary envelopment by budding into the perinuclear space, de-envelopment into the cytoplasm, cytoplasmic reenvelopment, and translocation of enveloped virions to extracellular spaces. UL20/gK-null viruses are blocked in cytoplasmic virion envelopment and egress, as indicated by an accumulation of unenveloped or partially enveloped capsids in the cytoplasm. Similarly, UL11-null mutants accumulate unenveloped capsids in the cytoplasm.