scholarly journals ArxA From Azoarcus sp. CIB, an Anaerobic Arsenite Oxidase From an Obligate Heterotrophic and Mesophilic Bacterium

2019 ◽  
Vol 10 ◽  
Author(s):  
Gonzalo Durante-Rodríguez ◽  
Helga Fernández-Llamosas ◽  
Elena Alonso-Fernandes ◽  
María Nieves Fernández-Muñiz ◽  
Riansares Muñoz-Olivas ◽  
...  
Keyword(s):  
Arsenite Oxidase ◽  
Mesophilic Bacterium

Complex between the subtilisin from a mesophilic bacterium and the Leech inhibitor eglin-C

1991 ◽  
Vol 47 (5) ◽  
pp. 707-730 ◽  
Author(s):  
Z. Dauter ◽  
C. Betzel ◽  
N. Genov ◽  
N. Pipon ◽  
K. S. Wilson
Keyword(s):  
Eglin C ◽  
Mesophilic Bacterium

Optimization and partial purification of a high-activity lipase synthesized by a newly isolated Acinetobacter from offshore waters of the Caspian Sea under solid-state fermentation

RSC Advances ◽  
2015 ◽  
Vol 5 (16) ◽  
pp. 12052-12061 ◽  
Author(s):  
Samira Moradi ◽  
Seyed Hadi Razavi ◽  
Seyyed Mohammad Mousavi ◽  
Seyed Mohammad Taghi Gharibzahedi
Keyword(s):  
Solid State ◽  
High Activity ◽  
Solid State Fermentation ◽  
Coastal Waters ◽  
Caspian Sea ◽  
Partial Purification ◽  
Extracellular Lipase ◽  
The Caspian Sea ◽  
Mesophilic Bacterium

A new aerobic mesophilic bacterium was isolated from the southern coastal waters of the Caspian Sea which substantially produced an extracellular lipase in solid-state fermentation using milled coriander seeds (MCS) as support substrate.

scholarly journals An AMP nucleosidase gene knockout in Escherichia coli elevates intracellular ATP levels and increases cold tolerance

2007 ◽  
Vol 4 (1) ◽  
pp. 53-56 ◽  
Author(s):  
Brittany A Morrison ◽  
Daniel H Shain
Keyword(s):  
Escherichia Coli ◽  
Steady State ◽  
Atp Hydrolysis ◽  
Gene Knockout ◽  
Compensatory Mechanism ◽  
Wild Type ◽  
Intracellular Atp ◽  
Atp Levels ◽  
Glacier Ice ◽  
Mesophilic Bacterium

Disparate psychrophiles (e.g. glacier ice worms, bacteria, algae and fungi) elevate steady-state intracellular ATP levels as temperatures decline, which has been interpreted as a compensatory mechanism to offset reductions in molecular motion and Gibb's free energy of ATP hydrolysis. In this study, we sought to manipulate steady-state ATP levels in the mesophilic bacterium, Escherichia coli , to investigate the relationship between cold temperature survivability and elevated intracellular ATP. Based on known energetic pathways and feedback loops, we targeted the AMP nucleotidase ( amn ) gene, which is thought to encode the primary AMP degradative enzyme in prokaryotes. By knocking out amn in wild-type E. coli DY330 cells using recombineering methodology, we generated a mutant (AMNk) that elevated intracellular ATP levels by more than 30% across its viable temperature range. As temperature was lowered, the relative ATP disparity between AMNk and DY330 cells increased to approximately 66% at 10°C, and was approximately 100% after storage at 0°C for 5–7 days. AMNk cells stored at 0°C for 7 days displayed approximately fivefold higher cell viability than wild-type DY330 cells treated in the same manner.

Constitutive arsenite oxidase expression detected in arsenic-hypertolerant Pseudomonas xanthomarina S11

2015 ◽  
Vol 166 (3) ◽  
pp. 205-214 ◽  
Author(s):  
Sandrine Koechler ◽  
Florence Arsène-Ploetze ◽  
Céline Brochier-Armanet ◽  
Florence Goulhen-Chollet ◽  
Audrey Heinrich-Salmeron ◽  
...  
Keyword(s):  
Arsenite Oxidase

scholarly journals Draft Genome Sequence of Syntrophomonas wolfei subsp. methylbutyratica Strain 4J5 T (JCM 14075), a Mesophilic Butyrate- and 2-Methylbutyrate-Degrading Syntroph

2016 ◽  
Vol 4 (2) ◽  
Author(s):  
Takashi Narihiro ◽  
Masaru K. Nobu ◽  
Hideyuki Tamaki ◽  
Yoichi Kamagata ◽  
Wen-Tso Liu
Keyword(s):  
Genome Sequence ◽  
Draft Genome ◽  
Draft Genome Sequence ◽  
Syntrophomonas Wolfei ◽  
Mesophilic Bacterium

Syntrophomonas wolfei subsp. methylbutyratica strain 4J5 T (=JCM 14075 T ) is a mesophilic bacterium capable of degrading butyrate and 2-methylbutyrate through syntrophic cooperation with a partner methanogen. The draft genome sequence is 3.2 Mb, with a G+C content of 45.5%.

scholarly journals Molybdenum-Containing Arsenite Oxidase of the Chemolithoautotrophic Arsenite Oxidizer NT-26

2004 ◽  
Vol 186 (6) ◽  
pp. 1614-1619 ◽  
Author(s):  
Joanne M. Santini ◽  
Rachel N. vanden Hoven
Keyword(s):  
Secretory Pathway ◽  
Alcaligenes Faecalis ◽  
Sequence Analyses ◽  
Arsenite Oxidase ◽  
Sulfolobus Tokodaii ◽  
Aeropyrum Pernix ◽  
Native Molecular Mass ◽  
Iron Sulfur ◽  
Dimethyl Sulfoxide Reductase

ABSTRACT The chemolithoautotroph NT-26 oxidizes arsenite to arsenate by using a periplasmic arsenite oxidase. Purification and preliminary characterization of the enzyme revealed that it (i) contains two heterologous subunits, AroA (98 kDa) and AroB (14 kDa); (ii) has a native molecular mass of 219 kDa, suggesting an α2β2 configuration; and (iii) contains two molybdenum and 9 or 10 iron atoms per α2β2 unit. The genes that encode the enzyme have been cloned and sequenced. Sequence analyses revealed similarities to the arsenite oxidase of Alcaligenes faecalis, the putative arsenite oxidase of the beta-proteobacterium ULPAs1, and putative proteins of Aeropyrum pernix, Sulfolobus tokodaii, and Chloroflexus aurantiacus. Interestingly, the AroA subunit was found to be similar to the molybdenum-containing subunits of enzymes in the dimethyl sulfoxide reductase family, whereas the AroB subunit was found to be similar to the Rieske iron-sulfur proteins of cytochrome bc 1 and b 6 f complexes. The NT-26 arsenite oxidase is probably exported to the periplasm via the Tat secretory pathway, with the AroB leader sequence used for export. Confirmation that NT-26 obtains energy from the oxidation of arsenite was obtained, as an aroA mutant was unable to grow chemolithoautotrophically with arsenite. This mutant could grow heterotrophically in the presence of arsenite; however, the arsenite was not oxidized to arsenate.

scholarly journals Heterologously expressed arsenite oxidase: A system to study biogenesis and structure/function relationships of the enzyme family

2012 ◽  
Vol 1817 (9) ◽  
pp. 1701-1708 ◽  
Author(s):  
Robert van Lis ◽  
Wolfgang Nitschke ◽  
Thomas P. Warelow ◽  
Line Capowiez ◽  
Joanne M. Santini ◽  
...  
Keyword(s):  
Structure Function ◽  
Arsenite Oxidase ◽  
Enzyme Family

scholarly journals Flux Analysis of the Metabolism ofClostridium cellulolyticum Grown in Cellulose-Fed Continuous Culture on a Chemically Defined Medium under Ammonium-Limited Conditions

2001 ◽  
Vol 67 (9) ◽  
pp. 3846-3851 ◽  
Author(s):  
Mickaël Desvaux ◽  
Henri Petitdemange
Keyword(s):  
Cellulose Degradation ◽  
Lactate Production ◽  
Nitrogen Sources ◽  
Maximum Growth ◽  
Defined Medium ◽  
Flux Analysis ◽  
Specific Rate ◽  
Cellulolytic Bacteria ◽  
Limiting Nutrient ◽  
Mesophilic Bacterium

ABSTRACT An investigation of cellulose degradation by the nonruminal, cellulolytic, mesophilic bacterium Clostridium cellulolyticum was performed in cellulose-fed chemostat cultures with ammonium as the growth-limiting nutrient. At any dilution rate (D), acetate was always the main product of the catabolism, with a yield of product from substrate ranging between 37.7 and 51.5 g per mol of hexose equivalent fermented and an acetate/ethanol ratio always higher than 1. AsD rose, the acetyl coenzyme A was rerouted in favor of ethanol pathways, and ethanol production could represent up to 17.7% of the carbon consumed. Lactate was significantly produced, but with increasing D, the specific lactate production rate declined, as did the specific rate of production of extracellular pyruvate. The proportion of the original carbon directed towards phosphoglucomutase remained constant, and the carbon surplus was balanced mainly by exopolysaccharide and glycogen biosyntheses at highD values, while cellodextrin excretion occurred mainly at lower ones. With increasing D, the specific rate of carbon flowing down catabolites increased as well, but when expressed as a percentage of carbon it declined, while the percentage of carbon directed through biosynthesis pathways was enhanced. The maximum growth and energetic yields were lower than those obtained in cellulose-limited chemostats and were related to an uncoupling between catabolism and anabolism leading to an excess of energy. Compared to growth on cellobiose in ammonium-limited chemostats (E. Guedon, M. Desvaux, and H. Petitdemange, J. Bacteriol. 182:2010–2017, 2000), (i) a specific consumption rate of carbon of as high as 26.72 mmol of hexose equivalent g of cells−1h−1 could not be reached and (ii) the proportions of carbon directed towards cellodextrin, glycogen, and exopolysaccharide pathways were not as high as first determined on cellobiose. While the use of cellobiose allows highlighting of metabolic limitation and regulation of C. cellulolyticumunder ammonium-limited conditions, some of these events should then rather be interpreted as distortions of the metabolism. Growth of cellulolytic bacteria on easily available carbon and nitrogen sources represents conditions far different from those of the natural lignocellulosic compounds.

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