scholarly journals Gene Cloning and Characterization of Two NADH-Dependent 3-Quinuclidinone Reductases from Microbacterium luteolum JCM 9174

2012 ◽  
Vol 79 (4) ◽  
pp. 1378-1384 ◽  
Author(s):  
Kentaro Isotani ◽  
Junji Kurokawa ◽  
Fumiko Suzuki ◽  
Syunsuke Nomoto ◽  
Takashi Negishi ◽  
...  

ABSTRACTWe used the resting-cell reaction to screen approximately 200 microorganisms for biocatalysts which reduce 3-quinuclidinone to optically pure (R)-(−)-3-quinuclidinol.Microbacterium luteolumJCM 9174 was selected as the most suitable organism. The genes encoding the protein products that reduced 3-quinuclidinone were isolated fromM. luteolumJCM 9174. ThebacCgene, which consists of 768 nucleotides corresponding to 255 amino acid residues and is a constituent of the bacilysin synthetic gene cluster, was amplified by PCR based on homology to known genes. Theqnrgene consisted of 759 nucleotides corresponding to 252 amino acid residues. Both enzymes belong to the short-chain alcohol dehydrogenase/reductase (SDR) family. The genes were expressed inEscherichia colias proteins which were His tagged at the N terminus, and the recombinant enzymes were purified and characterized. Both enzymes showed narrow substrate specificity and high stereoselectivity for the reduction of 3-quinuclidinone to (R)-(−)-3-quinuclidinol.

2012 ◽  
Vol 554-556 ◽  
pp. 1116-1120 ◽  
Author(s):  
Mei Rong Chen ◽  
Xing Shen ◽  
Lin Li ◽  
Song Qing Hu

Three low molecular weight subunit genes, named LMW-CND1 (GeneBank accession JQ780048), LMW-CND2 (GeneBank accession JQ779840), LMW-CND3 (GeneBank accession JQ779841), with a ORF of 1053 bp, 903 bp, 969 bp, respectively, were isolated from cv. Cheyenne and characterized detailed in molecular level. The proteins encoded by the genes, with 350, 300, 322 amino acid residues respectively, differ only in repetitive domain of sequences due to insertion or deletion of repeats in this domain. Highly similarity in amino-acid sequence between these three subunits and other published LMW-GSs was also observed, showing that all three genes published here are typical LMW-GS genes and closely related to the genes on chromosome 1D. Besides, secondary structure prediction of proteins indicated that, in the three LMW-GSs, random loop accounts for no less than 70 %, α-helix amounts to 26 %, average, and only 1.4 %~1.7 % is β-sheet.


BMC Genomics ◽  
2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Zhongying Wang ◽  
Qixuan Wang ◽  
Hao Wu ◽  
Zhiwu Huang

Abstract Background Prestin (SLC26A5) is responsible for acute sensitivity and frequency selectivity in the vertebrate auditory system. Limited knowledge of prestin is from experiments using site-directed mutagenesis or domain-swapping techniques after the amino acid residues were identified by comparing the sequence of prestin to those of its paralogs and orthologs. Frog prestin is the only representative in amphibian lineage and the studies of it were quite rare with only one species identified. Results Here we report a new coding sequence of SLC26A5 for a frog species, Rana catesbeiana (the American bullfrog). In our study, the SLC26A5 gene of Rana has been mapped, sequenced and cloned successively using RNA-Seq. We measured the nonlinear capacitance (NLC) of prestin both in the hair cells of Rana’s inner ear and HEK293T cells transfected with this new coding gene. HEK293T cells expressing Rana prestin showed electrophysiological features similar to that of hair cells from its inner ear. Comparative studies of zebrafish, chick, Rana and an ancient frog species showed that chick and zebrafish prestin lacked NLC. Ancient frog’s prestin was functionally different from Rana. Conclusions We mapped and sequenced the SLC26A5 of the Rana catesbeiana from its inner ear cDNA using RNA-Seq. The Rana SLC26A5 cDNA was 2292 bp long, encoding a polypeptide of 763 amino acid residues, with 40% identity to mammals. This new coding gene could encode a functionally active protein conferring NLC to both frog HCs and the mammalian cell line. While comparing to its orthologs, the amphibian prestin has been evolutionarily changing its function and becomes more advanced than avian and teleost prestin.


2004 ◽  
Vol 186 (15) ◽  
pp. 4885-4893 ◽  
Author(s):  
Takane Katayama ◽  
Akiko Sakuma ◽  
Takatoshi Kimura ◽  
Yutaka Makimura ◽  
Jun Hiratake ◽  
...  

ABSTRACT A genomic library of Bifidobacterium bifidum constructed in Escherichia coli was screened for the ability to hydrolyze the α-(1→2) linkage of 2′-fucosyllactose, and a gene encoding 1,2-α-l-fucosidase (AfcA) was isolated. The afcA gene was found to comprise 1,959 amino acid residues with a predicted molecular mass of 205 kDa and containing a signal peptide and a membrane anchor at the N and C termini, respectively. A domain responsible for fucosidase activity (the Fuc domain; amino acid residues 577 to 1474) was localized by deletion analysis and then purified as a hexahistidine-tagged protein. The recombinant Fuc domain specifically hydrolyzed the terminal α-(1→2)-fucosidic linkages of various oligosaccharides and a sugar chain of a glycoprotein. The stereochemical course of the hydrolysis of 2′-fucosyllactose was determined to be inversion by using 1H nuclear magnetic resonance. The primary structure of the Fuc domain exhibited no similarity to those of any glycoside hydrolases (GHs) but showed high similarity to those of several hypothetical proteins in a database. Thus, it was revealed that the AfcA protein constitutes a novel inverting GH family (GH family 95).


2013 ◽  
Vol 80 (4) ◽  
pp. 1482-1488 ◽  
Author(s):  
Jing Yang ◽  
Chao Wang ◽  
Jinyu Wu ◽  
Li Liu ◽  
Gang Zhang ◽  
...  

ABSTRACTThe genusExiguobacteriumcan adapt readily to, and survive in, diverse environments. Our study demonstrated thatExiguobacteriumsp. strain S3-2, isolated from marine sediment, is resistant to five antibiotics. The plasmid pMC1 in this strain carries seven putative resistance genes. We functionally characterized these resistance genes inEscherichia coli, and genes encoding dihydrofolate reductase and macrolide phosphotransferase were considered novel resistance genes based on their low similarities to known resistance genes. The plasmid G+C content distribution was highly heterogeneous. Only the G+C content of one block, which shared significant similarity with a plasmid fromExiguobacterium arabatum, fit well with the mean G+C content of the host. The remainder of the plasmid was composed of mobile elements with a markedly lower G+C ratio than the host. Interestingly, five mobile elements located on pMC1 showed significant similarities to sequences found in pathogens. Our data provided an example of the link between resistance genes in strains from the environment and the clinic and revealed the aggregation of antibiotic resistance genes in bacteria isolated from fish farms.


2015 ◽  
Vol 59 (9) ◽  
pp. 5357-5365 ◽  
Author(s):  
Hilde Smith ◽  
Alex Bossers ◽  
Frank Harders ◽  
Guanghui Wu ◽  
Neil Woodford ◽  
...  

ABSTRACTThe aim of the study was to identify the plasmid-encoded factors contributing to the emergence and spread of epidemic IncI1-Iγ plasmids obtained fromEscherichia coliandSalmonella entericaisolates from animal and human reservoirs. For this, 251 IncI1-Iγ plasmids carrying various extended-spectrum β-lactamase (ESBL) or AmpC β-lactamase genes were compared using plasmid multilocus sequence typing (pMLST). Thirty-two of these plasmids belonging to different pMLST types were sequenced using Roche 454 and Illumina platforms. Epidemic IncI1-Iγ plasmids could be assigned to various dominant clades, whereas rarely detected plasmids clustered together as a distinct clade. Similar phylogenetic trees were obtained using only the plasmid backbone sequences, showing that the differences observed between the plasmids belonging to distinct clades resulted mainly from differences between their backbone sequences. Plasmids belonging to the various clades differed particularly in the presence/absence of genes encoding partitioning and addiction systems, which contribute to stable inheritance during cell division and plasmid maintenance. Despite this, plasmids belonging to the various phylogenetic clades also showed marked resistance gene associations, indicating the circulation of successful plasmid-gene combinations. The variation intraYandexcAgenes found in IncI1-Iγ plasmids is conserved within pMLST sequence types and plays a role in incompatibility, although functional study is needed to elucidate the role of these genes in plasmid epidemiology.


2021 ◽  
Vol 42 (1) ◽  
pp. 14-23
Author(s):  
B.B. Patnaik ◽  
◽  
S. Baliarsingh ◽  
S. Sahoo ◽  
J.M. Chung ◽  
...  

Aim: Identification of full-length ORF of hemocyanin subunit-1 (Mr_HC_1) from the hepatopancreas transcriptome of freshwater prawn, Macrobrachium rosenbergii infected with Vibrio harveyi and characterization of its sequence and structure by in silico tools and softwares. Methodology: Illumina HiSeq and de novo assembled unigenes were scanned against PANM-DB to screen Mr_HC_1. FGENESH gene prediction and SMART programs were used to predict the ORF region. Subsequently, Clustal X2 and MEGA in-silico tools were used to understand the sequence relatedness and evolutionary status of Mr_HC_1. Structural prediction was performed by SWISS-MODEL and Ramachandran plot modeling programs Results: The full-length ORF was 1983 bp in length encoding a polypeptide of 661 amino acid residues. Mr_HC_1 showed a putative signal peptide of 21 amino acid residues at the N-terminus and three hemocyanin domains. Homology analysis of Mr_HC_1 amino acid sequence confirms maximum identity to M. nipponense hemocyanin subunit-1 (Mn_HC_1). Phylogenetic analysis showed that Mr_HC_1 is more closely related to the hemocyanin γ-type subunit of freshwater shrimps. Homology modeling of Mr_HC_1 showed homo-hexameric protein containing 12 copper ions. With a QMEAN score of -3.33 and model-template sequence identity of 59.15%, the predicted model of Mr_HC_1 is convincing Interpretation: This study characterizes the hemocyanin γ-type subunit protein of freshwater prawn, M. rosenbergii for future studies on host defense mechanisms.


2015 ◽  
Vol 39 (5) ◽  
pp. 3319-3326 ◽  
Author(s):  
Madhusudana M. B. Reddy ◽  
K. Basuroy ◽  
S. Chandrappa ◽  
B. Dinesh ◽  
B. Vasantha ◽  
...  

γn amino acid residues can be incorporated into structures in γn and hybrid sequences containing folded and extended α and δ residues.


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