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Full-Text Articles in Life Sciences
Purification And Characterization Of Novel Nucleases From A Thermophilic Fungus, Kyle Landry
Purification And Characterization Of Novel Nucleases From A Thermophilic Fungus, Kyle Landry
Kyle S Landry
A thermophilic fungus was isolated from composted horse manure. The organism was as a Chaetomium sp. by sequencing the highly conserved ITS region of the fungus and comparing to known regions in a genomic database and was referred to as TM-417. TM-417 was found to have an optimal growth temperature of 45 oC and an optimal pH of 7.0. An extracellular DNase and RNase was found to be produced by the isolate and were purified 145.58-fold and 127.6-fold respectively using a combination of size exclusion chromatography and a novel affinity membrane purification system. The extent of purification was determined …
Proteomic Analysis Of 17Β-Estradiol Degradation By Stenotrophomonas Maltophilia, Zhongtian Li
Proteomic Analysis Of 17Β-Estradiol Degradation By Stenotrophomonas Maltophilia, Zhongtian Li
Z Li
Microbial degradation plays a critical role in determining the environmental fate of steroid hormones, such as 17β-estradiol (E2). The molecular mechanisms governing the microbial transformation of E2 and its primary degradation intermediate, estrone (E1), are largely unknown. The objective of this study was to identify metabolism pathways that might be involved in microbial estrogen degradation. To achieve the objective, Stenotrophomonas maltophilia strain ZL1 was used as a model estrogen degrading bacterium and its protein expression level during E2/E1 degradation was studied using quantitative proteomics. During an E2 degradation experiment, strain ZL1 first converted E2 to E1 stoichiometrically. At 16 h …
A New Class Of Homoserine Lactone Quorum-Sensing Signals, Amy Schaefer, E Greenberg, Colin Oliver, Yasuhiro Oda, Jean Huang, Gili Bittan-Banin, Caroline Peres, Silke Schmidt, Katarina Juhaszova, Janice Sufrin, Caroline Harwood
A New Class Of Homoserine Lactone Quorum-Sensing Signals, Amy Schaefer, E Greenberg, Colin Oliver, Yasuhiro Oda, Jean Huang, Gili Bittan-Banin, Caroline Peres, Silke Schmidt, Katarina Juhaszova, Janice Sufrin, Caroline Harwood
Jean J. Huang
Quorum sensing is a term used to describe cell-to-cell communication that allows cell-density-dependent gene expression. Many bacteria use acyl-homoserine lactone (acyl-HSL) synthases to generate fatty acyl-HSL quorum-sensing signals, which function with signal receptors to control expression of specific genes. The fatty acyl group is derived from fatty acid biosynthesis and provides signal specificity, but the variety of signals is limited. Here we show that the photosynthetic bacterium Rhodopseudomonas palustris uses an acyl-HSL synthase to produce p-coumaroyl-HSL by using environmental p-coumaric acid rather than fatty acids from cellular pools. The bacterium has a signal receptor with homology to fatty acyl-HSL receptors …
Acyl‐Hsl Signal Decay: Intrinsic To Bacterial Cell–Cell Communications, Ya-Juan Wang, Jean Huang, Jared Leadbetter
Acyl‐Hsl Signal Decay: Intrinsic To Bacterial Cell–Cell Communications, Ya-Juan Wang, Jean Huang, Jared Leadbetter
Jean J. Huang
No abstract available.
The Acid Stress Response Of The Cyanobacterium Synechocystis Sp. Strain Pcc 6308, Jean Huang, Nancy Kolodny, Jennifer Redfearn, Mary Allen
The Acid Stress Response Of The Cyanobacterium Synechocystis Sp. Strain Pcc 6308, Jean Huang, Nancy Kolodny, Jennifer Redfearn, Mary Allen
Jean J. Huang
The cyanobacterium Synechocystis sp. strain PCC 6308 has been shown to exhibit predictable physiological responses to acid stress. Originally isolated from a Wisconsin lake, this cyanobacterium grows optimally under alkaline conditions in the laboratory. After acid stress at a pH of between 4.4 and 7.7, cells return to exponential growth following a lag phase. The organism's response to this tolerable acid stress involves cell concentration-dependent neutralization of the external medium to pH 6 or above within 5 min, maintenance of a transmembrane pH gradient, and maintenance of photosystem II efficiency. Lethal acid stress, at a pH below 4.4, results in …
Removing 17Β-Estradiol From Drinking Water In A Biologically Active Carbon (Bac) Reactor Modified From A Granular Activated Carbon (Gac) Reactor, Zhongtian Li
Z Li
Estrogenic compounds in drinking water sources pose potential threats to human health. Treatment technologies are needed to effectively remove these compounds for the production of safe drinking water. In this study, GAC adsorption was first tested for its ability to remove a model estrogenic compound, 17β-estradiol (E2). Although GAC showed a relatively high adsorption capacity for E2 in isotherm experiments, it appeared to have a long mass transfer zone in a GAC column reactor, causing an early leakage of E2 in the effluent. With an influent E2 concentration of 20 μg/L, the GAC reactor was able to bring down effluent …
Do Larval Traits Re-Evolve? Evidence From The Embryogenesis Of A Direct-Developing Salamander, Plethodon Cinereus, Ryan Kerney, David Blackburn, Hendrik Muller, James Hanken
Do Larval Traits Re-Evolve? Evidence From The Embryogenesis Of A Direct-Developing Salamander, Plethodon Cinereus, Ryan Kerney, David Blackburn, Hendrik Muller, James Hanken
Ryan Kerney
Recent molecular phylogenies suggest the surprising reacquisition of posthatching metamorphosis within an otherwise directdeveloping clade of lungless salamanders (family Plethodontidae). Metamorphosis was long regarded as plesiomorphic for plethodontids, yet the genus Desmognathus, which primarily includes metamorphosing species, is now nested within a much larger clade of direct-developing species. The extent to which the putative reacquisition of metamorphosis in Desmognathus represents a true evolutionary reversal is contingent upon the extent to which both larva-specific features and metamorphosis were actually lost during the evolution of direct development. In this study we analyze development of the hyobranchial skeleton, which is dramatically remodeled during …