Specificity of Triamineoxidease

The substrate-specificity of a newly described enzyme common to six bacterial species, comprising five different genera, isolated from such widely divergent sources as decomposing fish, well-water and surface taint butter, was investigated. Of the various substrates studied only trialkylamine oxides having the general structure R3 ≡≡ N = 0 were activated with subsequent reduction, the corresponding volatile base being formed in each case. Betaine, choline, acetylcholine, ergothioneine and stachydrine containing an atomic group similar to the above were not activated. The designation "triamineoxidease" is proposed for this enzyme.

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Evolution of substrate specificity in a retained enzyme driven by gene loss

eLife ◽

10.7554/elife.22679 ◽

2017 ◽

Vol 6 ◽

Cited By ~ 13

Author(s):

Ana Lilia Juárez-Vázquez ◽

Janaka N Edirisinghe ◽

Ernesto A Verduzco-Castro ◽

Karolina Michalska ◽

Chenggang Wu ◽

...

Keyword(s):

Substrate Specificity ◽

Gene Loss ◽

Bacterial Species ◽

Purifying Selection ◽

Metabolic Modeling ◽

Functional Adaptation ◽

X Ray ◽

Functional Changes ◽

Dual Substrate

The connection between gene loss and the functional adaptation of retained proteins is still poorly understood. We apply phylogenomics and metabolic modeling to detect bacterial species that are evolving by gene loss, with the finding that Actinomycetaceae genomes from human cavities are undergoing sizable reductions, including loss of L-histidine and L-tryptophan biosynthesis. We observe that the dual-substrate phosphoribosyl isomerase A or priA gene, at which these pathways converge, appears to coevolve with the occurrence of trp and his genes. Characterization of a dozen PriA homologs shows that these enzymes adapt from bifunctionality in the largest genomes, to a monofunctional, yet not necessarily specialized, inefficient form in genomes undergoing reduction. These functional changes are accomplished via mutations, which result from relaxation of purifying selection, in residues structurally mapped after sequence and X-ray structural analyses. Our results show how gene loss can drive the evolution of substrate specificity from retained enzymes.

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Molecular detection of opportunistic pathogens and insights into microbial diversity in private well water and premise plumbing

Journal of Water and Health ◽

10.2166/wh.2020.271 ◽

2020 ◽

Vol 18 (5) ◽

pp. 820-834

Author(s):

Jia Xue ◽

Bowen Zhang ◽

Jennifer Lamori ◽

Kinjal Shah ◽

Jovanny Zabaleta ◽

...

Keyword(s):

Health Risk ◽

Rural Areas ◽

Bacterial Species ◽

Human Health Risk ◽

Total Coliform ◽

Water Systems ◽

Well Water ◽

Target Sequence ◽

Opportunistic Pathogens ◽

Fecal Indicator

Abstract Private well water systems in rural areas that are improperly maintained will result in poor drinking water quality, loss of water supply, and pose human health risk. The purpose of this study was to investigate the occurrence of fecal indicator bacteria (FIB) and opportunistic pathogens in private well water in rural areas surrounding New Orleans, Louisiana. Our results confirmed the ubiquitous nature of Legionella (86.7%) and mycobacteria (68.1%) in private well water in the study area, with gene concentration ranged from 0.60 to 5.53 and 0.67 to 5.95 Log10 of GC/100 mL, respectively. Naegleria fowleri target sequence was detected in 16.8% and Escherichia coli was detected in 43.4% of the water samples. Total coliform, as well as Legionella and mycobacteria genetic markers' concentrations were significantly reduced by 3-minute flushing. Next-generation sequencing (NGS) data indicated that the abundance of bacterial species was significantly increased in water collected in kitchens compared with samples from wells directly. This study provided integrated knowledge on the persistence of pathogenic organisms in private well water. Further study is needed to explore the presence of clinical species of those opportunistic pathogens in private well water systems to elucidate the health risk.

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Purification and Application of Lipases from Pseudomonas Species

Biological Sciences - PJSIR ◽

10.52763/pjsir.biol.sci.59.2.2016.111.116 ◽

2016 ◽

Vol 59 (2) ◽

pp. 111-116

Author(s):

Saadat Ullah ◽

Ijaz Malook ◽

Khair Ul Bashar ◽

Mehvish Riaz ◽

Muhammad Mudasar Aslam ◽

...

Keyword(s):

Fatty Acids ◽

Pseudomonas Aeruginosa ◽

Substrate Specificity ◽

Large Scale ◽

Bacterial Species ◽

Hydrolytic Enzymes ◽

Broad Substrate Specificity ◽

Industrial Sectors ◽

Pseudomonas Species ◽

Long Chain

Lipases are important hydrolytic enzymes that hydrolyze long chain triacylglycerol intodiacylglycerol, monoacylglycerol, glycerol and fatty acids. Lipases are found in microorganisms, fungi,plants and animals. Commercially, useful extracellular lipases are isolated from different bacterial species,including Bacillus, Achromobacter, Alcaligenes, Arthrobacter, Pseudomonas, Staphylococcus andChromobacterium species. Among the Pseudomonas species, Pseudomonas aeruginosa, P. cepacia andP. fluorescence are the major producers of lipases. Bacterial lipases have great industrial applicationsbecause of their stability, selectivity and broad substrate specificity. Due to their large scale applicationin industrial sectors, attention is given to isolate Pseudomonas lipases. In this review, purification strategiesfor lipases isolated from Pseudomonas species have been focussed.

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Functional phenotyping of small multidrug resistance proteins from Staphylococcus aureus and Francisella tularensis reveals functional homology to EmrE

10.1101/2021.01.06.425668 ◽

2021 ◽

Author(s):

Peyton J Spreacker ◽

Will F Beeninga ◽

Brooke L Young ◽

Colin J Porter ◽

Katherine A Henzler-Wildman

Keyword(s):

Staphylococcus Aureus ◽

Multidrug Resistance ◽

Substrate Specificity ◽

Francisella Tularensis ◽

Bacterial Species ◽

Toxic Metabolite ◽

Bacterial Cells ◽

Multidrug Resistance Proteins ◽

Antibiotic Development ◽

Small Multidrug Resistance

Small multidrug resistance (SMR) transporters efflux toxic substrates from bacterial cells. These transporters were recently divided into two subfamilies: the GdX-like and EmrE-like SMRs. The EmrE-like subfamily of SMRs is predicted to contain transporters that are highly promiscuous in both substrate specificity and mechanism based on extensive characterization of the founding member of this subfamily, EmrE. However, there is only limited functional analysis of other members of this family from pathogenic strains such as Staphylococcus aureus and Francisella tularensis. Here, we use a small compound screen to explore the substrate specificity and diversity of EmrE-subfamily SMRs from these two bacterial species and confirm that they are functionally more like EmrE than the GdX-like subfamily of toxic-metabolite transporters. The results of these experiments lay the foundation for understanding the complex substrate specificity profiles of SMR family transporters and assess the potential for targeting these transporters for future antibiotic development, either broadly or in a species-specific manner.

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Structural analysis of the photosynthetic membrane from Ectothiorhodospira halochloris

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010007727x ◽

1983 ◽

Vol 41 ◽

pp. 740-741

Author(s):

H. Engelhardt ◽

R. Guckenberger ◽

W. Baumeister

Keyword(s):

Lattice Structure ◽

Bacterial Species ◽

Hexagonal Lattice ◽

Reaction Centre ◽

Photosynthetic Membrane ◽

Rhodopseudomonas Viridis ◽

Photosynthetic Membranes ◽

Ectothiorhodospira Halochloris ◽

Main Components

Bacterial photosynthetic membranes contain, apart from lipids and electron transport components, reaction centre (RC) and light harvesting (LH) polypeptides as the main components. The RC-LH complexes in Rhodopseudomonas viridis membranes are known since quite seme time to form a hexagonal lattice structure in vivo; hence this membrane attracted the particular attention of electron microscopists. Contrary to previous claims in the literature we found, however, that 2-D periodically organized photosynthetic membranes are not a unique feature of Rhodopseudomonas viridis. At least five bacterial species, all bacteriophyll b - containing, possess membranes with the RC-LH complexes regularly arrayed. All these membranes appear to have a similar lattice structure and fine-morphology. The lattice spacings of the Ectothiorhodospira haloohloris, Ectothiorhodospira abdelmalekii and Rhodopseudomonas viridis membranes are close to 13 nm, those of Thiocapsa pfennigii and Rhodopseudomonas sulfoviridis are slightly smaller (∼12.5 nm).

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Silicon Substitution for Calcium in the Shell of the Fingernail Clam, Musculium Transversum Studied By X-Ray Analysis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s1431927600002488 ◽

1980 ◽

Vol 38 ◽

pp. 560-561

Author(s):

Judith A. Murphy ◽

Anthony Paparo ◽

Richard Sparks

Keyword(s):

Carbonic Anhydrase ◽

River Water ◽

Food Chains ◽

Well Water ◽

Shell Formation ◽

X Ray ◽

Molluscan Shell ◽

Fingernail Clams

Fingernail clams (Muscu1ium transversum) are dominant bottom-dwelling animals in some waters of the midwest U.S. These organisms are key links in food chains leading from nutrients in water and mud to fish and ducks which are utilized by man. In the mid-1950’s, fingernail clams disappeared from a 100-mile section of the Illinois R., a tributary of the Mississippi R. Some factor(s) in the river and/or sediment currently prevent clams from recolonizing areas where they were formerly abundant. Recently, clams developed shell deformities and died without reproducing. The greatest mortality and highest incidence of shell deformities appeared in test chambers containing the highest proportion of river water to well water. The molluscan shell consists of CaCO3, and the tissue concerned in its secretion is the mantle. The source of the carbonate is probably from metabolic CO2 and the maintenance of ionized Ca concentration in the mantle is controlled by carbonic anhydrase. The Ca is stored in extracellular concentric spherical granules(0.6-5.5μm) which represent a large amount of inertCa in the mantle. The purpose of this investigation was to examine the role of raw river water and well water on shell formation in the fingernail clam.

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Substrate specificity and inducibility of TACE (tumour necrosis factor α-converting enzyme) revisited: the Ala-Val preference, and induced intrinsic activity

Biochemical Society Symposium ◽

10.1042/bss0700039 ◽

2003 ◽

Vol 70 ◽

pp. 39-52 ◽

Cited By ~ 54

Author(s):

Roy A. Black ◽

John R. Doedens ◽

Rajeev Mahimkar ◽

Richard Johnson ◽

Lin Guo ◽

...

Keyword(s):

Substrate Specificity ◽

Recent Work ◽

Tumour Necrosis Factor ◽

Tumour Necrosis ◽

Transforming Growth Factor ◽

Intrinsic Activity ◽

Converting Enzyme ◽

Tumour Necrosis Factor Α ◽

Factor Α ◽

Necrosis Factor

Tumour necrosis factor α (TNFα)-converting enzyme (TACE/ADAM-17, where ADAM stands for a disintegrin and metalloproteinase) releases from the cell surface the extracellular domains of TNF and several other proteins. Previous studies have found that, while purified TACE preferentially cleaves peptides representing the processing sites in TNF and transforming growth factor α, the cellular enzyme nonetheless also sheds proteins with divergent cleavage sites very efficiently. More recent work, identifying the cleavage site in the p75 TNF receptor, quantifying the susceptibility of additional peptides to cleavage by TACE and identifying additional protein substrates, underlines the complexity of TACE-substrate interactions. In addition to substrate specificity, the mechanism underlying the increased rate of shedding caused by agents that activate cells remains poorly understood. Recent work in this area, utilizing a peptide substrate as a probe for cellular TACE activity, indicates that the intrinsic activity of the enzyme is somehow increased.

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