Read by QxMD icon Read


Kaizhu Zeng, Qian Li, Jing Wang, Guowei Yin, Yajun Zhang, Chaoni Xiao, Taiping Fan, Xinfeng Zhao, Xiaohui Zheng
Protein immobilization techniques play an important role in the development of assays for disease diagnosis and drug discovery. However, many of these approaches are not applicable to transmembrane proteins. G protein-coupled receptors (GPCRs) are the largest protein superfamily encoded by the human genome and are targeted by a quarter of all prescription drugs. GPCRs are highly dynamic and sensitive to changes in the ambient environment, and current immobilization methodologies are not suitable for GPCRs. We used haloalkane dehalogenase (Halo) as an immobilization tag fused to the β2 -adrenoceptor (β2 -AR), angiotensin II type 1 (AT1 ) and angiotensin II type 2 (AT2 ) receptors...
January 14, 2018: Chemical Science
Mohsen Behbahani, Boren Lin, Tamara L Phares, Youngwoo Seo
The objective of this study is to evaluate the influence of water distribution system conditions (pH, total organic carbon, residual chlorine, and phosphate) on haloacetic acids (HAAs) biodegradation. A series of batch microcosm tests were conducted to determine biodegradation kinetics and collected biomass was used for real time quantitative reverse transcription polymerase chain reaction analyses to monitor how these drinking water distribution system conditions affect the relative expression of bacterial dehalogenase genes...
March 3, 2018: Journal of Hazardous Materials
Lingdi Zhang, Hengbo Zhou, Xueni Li, Rebecca L Vartuli, Michael Rowse, Yongna Xing, Pratyaydipta Rudra, Debashis Ghosh, Rui Zhao, Heide L Ford
Eya genes encode a unique family of multifunctional proteins that serve as transcriptional co-activators and as haloacid dehalogenase-family Tyr phosphatases. Intriguingly, the N-terminal domain of Eyas, which does not share sequence similarity to any known phosphatases, contains a separable Ser/Thr phosphatase activity. Here, we demonstrate that the Ser/Thr phosphatase activity of Eya is not intrinsic, but arises from its direct interaction with the protein phosphatase 2A (PP2A)-B55α holoenzyme. Importantly, Eya3 alters the regulation of c-Myc by PP2A, increasing c-Myc stability by enabling PP2A-B55α to dephosphorylate pT58, in direct contrast to the previously described PP2A-B56α-mediated dephosphorylation of pS62 and c-Myc destabilization...
March 13, 2018: Nature Communications
Géraldine Florence Buttet, Alexandra Marie Murray, Tobias Goris, Mélissa Burion, Biao Jin, Massimo Rolle, Christof Holliger, Julien Maillard
Two anaerobic bacterial consortia, each harboring a distinct Sulfurospirillum population, were derived from a ten year old consortium, SL2, previously characterized for the stepwise dechlorination of tetrachloroethene (PCE) to cis-dichloroethene (cis-DCE) via accumulation of trichloroethene (TCE). Population SL2-1 dechlorinated PCE to TCE exclusively, while SL2-2 produced cis-DCE from PCE without substantial TCE accumulation. The reasons explaining the long-term coexistence of the populations were investigated...
March 6, 2018: FEMS Microbiology Ecology
Shubhangi Kaushik, Sérgio M Marques, Prashant Khirsariya, Kamil Paruch, Lenka Libichova, Jan Brezovsky, Zbynek Prokop, Radka Chaloupkova, Jiri Damborsky
The traditional way of rationally engineering enzymes to change their biocatalytic properties utilizes the modifications of their active sites. Another emerging approach is the engineering of structural features involved in the exchange of ligands between buried active sites and the surrounding solvent. However, surprisingly little is known about the effects of mutations that alter the access tunnels on the enzymes' catalytic properties, and how these tunnels should be redesigned to allow fast passage of cognate substrates and products...
February 25, 2018: FEBS Journal
Zhineng Wu, Miaomiao Xie, Yao Li, Guanghai Gao, Mark Bartlam, Yingying Wang
Polybrominated diphenyl ethers (PBDEs) have become widespread environmental pollutants all over the world. A newly isolated bacterium from an e-waste recycling area, Stenotrophomonas sp. strain WZN-1, can degrade decabromodiphenyl ether (BDE 209) effectively under aerobic conditions. Orthogonal test results showed that the optimum conditions for BDE 209 biodegradation were pH 5, 25 °C, 0.5% salinity, 150 mL minimal salt medium volume. Under the optimized condition, strain WZN-1 could degrade 55.15% of 65 μg/L BDE 209 under aerobic condition within 30 day incubation...
February 24, 2018: AMB Express
Qingying Lai, Wenbi Wu, Ao Li, Wei Wang, Meijin Yuan, Kai Yang
Encapsidation of the viral genomes, leading to the assembly of the nucleocapsids to form infectious progeny virions, is a key step in many virus life cycles. Baculovirus nucleocapsid assembly is a complex process that involves many proteins. Our previous studies showed that the deletion of the core gene, 38K ( ac98 ) interrupted the nucleocapsid assembly by producing capsid sheaths devoid of viral genomes under unknown mechanism. All homologs of 38K contain conserved motifs of the haloacid dehalogenase superfamily, which are involved in phosphoryl transfer...
February 14, 2018: Journal of Virology
Gretchen L W Heavner, Cresten B Mansfeldt, Garrett E Debs, Sage T Hellerstedt, Annette R Rowe, Ruth E Richardson
Using mRNA transcript levels for key functional enzymes as proxies for the organohalide respiration (OHR) rate, is a promising approach for monitoring bioremediation populations in situ at chlorinated solvent-contaminated field sites. However, to date, no correlations have been empirically derived for chlorinated solvent respiring, Dehalococcoides mccartyi (DMC) containing, bioaugmentation cultures. In the current study, genome-wide transcriptome and proteome data were first used to confirm the most highly expressed OHR-related enzymes in the bioaugmentation culture, KB-1TM, including several reductive dehalogenases (RDases) and a Ni-Fe hydrogenase, Hup...
February 8, 2018: Microorganisms
Shu-Ping Zou, Kai Gu, Yu-Guo Zheng
Halohydrin dehalogenase (HHDH)-mediated dehalogenation of 1,3-dichloro-2-propanol (1,3-DCP) is a key step in the chemoenzymatic synthesis of epichlorohydrin (ECH) from glycerol. In this study, a covalent immobilization strategy was employed to enhance the stability of Agrobacterium tumefaciens HHDH by using epoxy resin ES-103B as a carrier. Under optimal conditions, the activity recovery of ES-103B-immobilized HHDH (HHDH@ES-103B) was 62.4% and the specific activity was 1604 U/g. The HHDH@ES-103B exhibited excellent thermostability, with a half-life of 68...
February 1, 2018: Biotechnology Progress
Sebastian Keller, Cindy Kunze, Martin Bommer, Christian Paetz, Riya C Menezes, Aleš Svatoš, Holger Dobbek, Torsten Schubert
The organohalide-respiring bacterium Sulfurospirillum multivorans produces a unique cobamide, namely norpseudo-B12, which serves as cofactor of the tetrachloroethene (PCE) reductive dehalogenase (PceA). As previously reported, a replacement of the adeninyl-moiety, the lower base of the cofactor, by exogenously applied 5,6-dimethylbenzimidazole led to inactive PceA. To explore the general effect of benzimidazoles on the PCE metabolism, the susceptibility of the organism for guided biosynthesis of various singly substituted benzimidazolyl-norcobamides was investigated and their use as cofactor by PceA was analyzed...
January 29, 2018: Journal of Bacteriology
Bat-Erdene Jugder, Karl A P Payne, Karl Fisher, Susanne Bohl, Helene Lebhar, Mike Manefield, Matthew Lee, David Leys, Christopher P Marquis
Reductive dehalogenases (RDase) are key enzymes involved in the respiratory process of anaerobic organohalide respiring bacteria (ORB). Heterologous expression of respiratory RDases is desirable for structural and functional studies, however there are few reports of successful expression of these enzymes. Dehalobacter sp. strain UNSWDHB is an ORB, whose preferred electron acceptor is chloroform. This study describes efforts to express recombinant reductive dehalogenase (TmrA), derived from UNSWDHB, using the heterologous hosts Escherichia coli and Bacillus megaterium...
January 24, 2018: ACS Chemical Biology
Yayue Wang, Yanbin Feng, Xupeng Cao, Yinghui Liu, Song Xue
D-2-haloacid dehalogenases (D-DEXs) catalyse the hydrolytic dehalogenation of D-2-haloacids, releasing halide ions and producing the corresponding 2-hydroxyacids. A structure-guided elucidation of the catalytic mechanism of this dehalogenation reaction has not been reported yet. Here, we report the catalytic mechanism of a D-DEX, HadD AJ1 from Pseudomonas putida AJ1/23, which was elucidated by X-ray crystallographic analysis and the H2 18 O incorporation experiment. HadD AJ1 is an α-helical hydrolase that forms a homotetramer with its monomer including two structurally axisymmetric repeats...
January 23, 2018: Scientific Reports
Yukihiro Kitade, Ryoma Hashimoto, Masako Suda, Kazumi Hiraga, Masayuki Inui
Corynebacterium glutamicum was metabolically engineered to produce 4-hydroxybenzoic acid (4-HBA), a valuable aromatic compound used as a raw material for the production of liquid crystal polymers and paraben. C. glutamicum was found to have a higher tolerance to 4-HBA toxicity than previously reported hosts used for the production of genetically engineered 4-HBA. To obtain higher titers of 4-HBA, we employed a stepwise overexpression of all seven target genes in the shikimate pathway in C. glutamicum Specifically, multiple chromosomal integrations of a mutated aroG gene from Escherichia coli , encoding a 3-deoxy-d-arabinoheptulosonic acid 7-phosphate (DAHP) synthase, and wild-type aroCKB from C...
March 15, 2018: Applied and Environmental Microbiology
Andrew T Quaile, Peter J Stogios, Olga Egorova, Elena Evdokimova, Dylan Valleau, Boguslaw Nocek, Purnima S Kompella, Sergio Peisajovich, Alexander F Yakunin, Alexander W Ensminger, Alexei Savchenko
Host colonization by Gram-negative pathogens often involves delivery of bacterial proteins called "effectors" into the host cell. The pneumonia-causing pathogen Legionella pneumophila delivers more than 330 effectors into the host cell via its type IVB Dot/Icm secretion system. The collective functions of these proteins are the establishment of a replicative niche from which Legionella can recruit cellular materials to grow while evading lysosomal fusion inhibiting its growth. Using a combination of structural, biochemical, and in vivo approaches, we show that one of these translocated effector proteins, Ceg4, is a phosphotyrosine phosphatase harboring a haloacid dehalogenase-hydrolase domain...
March 2, 2018: Journal of Biological Chemistry
Shangwei Zhang, Lorenz Adrian, Gerrit Schüürmann
The bacterium Dehalococcoides, strain CBDB1, transforms aromatic halides through reductive dehalogenation. So far, however, the structures of its vitamin B12 -containing dehalogenases are unknown, hampering clarification of the catalytic mechanism and substrate specificity as basis for targeted remediation strategies. This study employs a quantum chemical donor-acceptor approach for the Co(I)-substrate electron transfer. Computational characterization of the substrate electron affinity at carbon-halogen bonds enables discriminating aromatic halides ready for dehalogenation by strain CBDB1 (active substrates) from nondehalogenated (inactive) counterparts with 92% accuracy, covering 86 of 93 bromobenzenes, chlorobenzenes, chlorophenols, chloroanilines, polychlorinated biphenyls, and dibenzo-p-dioxins...
February 20, 2018: Environmental Science & Technology
Lifeng Chen, Ed S Krol, Meena K Sakharkar, Haseeb A Khan, Abdullah S Alhomida, Jian Yang
Maleylacetate reductase (PcpE), the last enzyme in the pentachlorophenol biodegradation pathway in Sphingobium chlorophenolicum L-1, catalyzes two consecutive reductive reactions, reductive dehalogenation of 2-chloromaleylacetate (2-CMA) to maleylacetate (MA) and subsequent reduction of MA to 3-oxoadipate (3-OXO). In each reaction, one molecule of NADH is consumed. To better understand its catalytic function, we undertook a structural model-based site-directed mutagenesis and steady-state kinetics study of PcpE...
December 22, 2017: Scientific Reports
Qian Liao, Xuan Du, Wei Jiang, Yapei Tong, Zhipeng Zhao, Ruiqin Fang, Juan Feng, Lixia Tang
Halohydrin dehalogenase from Agrobacterium radiobacter AD1 (HheC) shows great potential to produce valuable optically pure epoxides and β-substituted alcohols. However, this enzyme has been reported to be very sensitive and less stable under oxidative conditions. Enzyme immobilization represents a powerful means to overcome this limitation and provides the enzyme characteristics of a biocatalyst. In this study, the crude extract of HheC was directly subjected to enzyme immobilization using a carrier-free cross-linked enzyme aggregates (CLEAs) method...
April 20, 2018: Journal of Biotechnology
Holly L Sewell, Anne-Kristin Kaster, Alfred M Spormann
The deep marine subsurface is one of the largest unexplored biospheres on Earth and is widely inhabited by members of the phylum Chloroflexi In this report, we investigated genomes of single cells obtained from deep-sea sediments of the Peruvian Margin, which are enriched in such Chloroflexi 16S rRNA gene sequence analysis placed two of these single-cell-derived genomes (DscP3 and Dsc4) in a clade of subphylum I Chloroflexi which were previously recovered from deep-sea sediment in the Okinawa Trough and a third (DscP2-2) as a member of the previously reported DscP2 population from Peruvian Margin site 1230...
December 19, 2017: MBio
Muhammad Farhan Ul Haque, Ludovic Besaury, Thierry Nadalig, Françoise Bringel, Jérôme Mutterer, Hubert Schaller, Stéphane Vuilleumier
Chloromethane (CH3 Cl) is a toxic gas mainly produced naturally, in particular by plants, and its emissions contribute to ozone destruction in the stratosphere. Conversely, CH3 Cl can be degraded and used as the sole carbon and energy source by specialised methylotrophic bacteria, isolated from a variety of environments including the phyllosphere, i.e. the aerial parts of vegetation. The potential role of phyllospheric CH3 Cl-degrading bacteria as a filter for plant emissions of CH3 Cl was investigated using variants of Arabidopsis thaliana with low, wild-type and high expression of HOL1 methyltransferase previously shown to be responsible for most of CH3 Cl emissions by A...
December 14, 2017: Scientific Reports
Won-Hee Jung, Ye-Eun Son, Sang-Hun Oh, Ci Fu, Hye Shin Kim, Jin-Hwan Kwak, Maria E Cardenas, Joseph Heitman, Hee-Soo Park
Calcineurin modulates environmental stress survival and virulence of the human fungal pathogen Cryptococcus neoformans Previously, we identified 44 putative calcineurin substrates, and proposed that the calcineurin pathway is branched to regulate targets including Crz1, Pbp1, and Puf4 in C. neoformans In this study, we characterized Had1, which is one of the putative calcineurin substrates belonging to the ubiquitously conserved haloacid dehalogenase β-phosphoglucomutase protein superfamily. Growth of the had1 ∆ mutant was found to be compromised at 38° or higher...
February 2, 2018: G3: Genes—Genomes—Genetics
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"