Characterization of the 450-kb Linear Plasmid in a Polychlorinated Biphenyl Degrader, Rhodococcus sp. Strain RHA1

ABSTRACT A strong polychlorinated biphenyl (PCB) degrader,Rhodococcus sp. strain RHA1, has diverse biphenyl/PCB degradative genes and harbors huge linear plasmids, including pRHL1 (1,100 kb), pRHL2 (450 kb), and pRHL3 (330 kb). The diverse degradative genes are distributed mainly on the pRHL1 and pRHL2 plasmids. In this study, the structural and functional characteristics of pRHL2 were determined. We constructed a physical map of pRHL2, and the degradative enzyme genes, including bphB2, etbD2, etbC, bphDEF, bphC2, and bphC4, were localized in three regions. Conjugal transfer of pRHL2 between RHA1 mutant derivatives was observed at a frequency of 7.5 × 10−5 transconjugant per recipient. These results suggested that the linear plasmid is a possible determinant of propagation of the diverse degradative genes in rhodococci. The termini of pRHL2 were cloned and sequenced. The left and right termini of pRHL2 had 3-bp perfect terminal inverted repeats and were not as similar to each other (64% identity) as the known actinomycete linear replicons are. Southern hybridization analysis with pRHL2 terminal probes suggested that the right terminus of pRHL2 is similar to pRHL1 and pRHL3 termini. Retardation of both terminal fragments in the gel shift assay indicated that each terminus of pRHL2 is linked to a protein. We suggest that pRHL2 has invertron termini, as has been reported previously for Streptomyces linear replicons.

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Lateralization of face processing in the human brain

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2011.1784 ◽

2012 ◽

Vol 279 (1735) ◽

pp. 2052-2061 ◽

Cited By ~ 84

Author(s):

Ming Meng ◽

Tharian Cherian ◽

Gaurav Singal ◽

Pawan Sinha

Keyword(s):

Face Processing ◽

Inhibitory Influence ◽

Hemispheric Differences ◽

Response Dynamics ◽

Activation Patterns ◽

Face Selectivity ◽

Left And Right ◽

The Right ◽

Processing Mechanisms

Are visual face processing mechanisms the same in the left and right cerebral hemispheres? The possibility of such ‘duplicated processing’ seems puzzling in terms of neural resource usage, and we currently lack a precise characterization of the lateral differences in face processing. To address this need, we have undertaken a three-pronged approach. Using functional magnetic resonance imaging, we assessed cortical sensitivity to facial semblance, the modulatory effects of context and temporal response dynamics. Results on all three fronts revealed systematic hemispheric differences. We found that: (i) activation patterns in the left fusiform gyrus correlate with image-level face-semblance, while those in the right correlate with categorical face/non-face judgements. (ii) Context exerts significant excitatory/inhibitory influence in the left, but has limited effect on the right. (iii) Face-selectivity persists in the right even after activity on the left has returned to baseline. These results provide important clues regarding the functional architecture of face processing, suggesting that the left hemisphere is involved in processing ‘low-level’ face semblance, and perhaps is a precursor to categorical ‘deep’ analyses on the right.

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Sequent-systems for modal logic

Journal of Symbolic Logic ◽

10.2307/2273797 ◽

1985 ◽

Vol 50 (1) ◽

pp. 149-168 ◽

Cited By ~ 29

Author(s):

Kosta Došen

Keyword(s):

Order Logic ◽

Philosophical Logic ◽

Logical Constants ◽

First Order ◽

Sequent Systems ◽

Left And Right ◽

Level 1 ◽

The Right ◽

Level 2

AbstractThe purpose of this work is to present Gentzen-style formulations of S5 and S4 based on sequents of higher levels. Sequents of level 1 are like ordinary sequents, sequents of level 2 have collections of sequents of level 1 on the left and right of the turnstile, etc. Rules for modal constants involve sequents of level 2, whereas rules for customary logical constants of first-order logic with identity involve only sequents of level 1. A restriction on Thinning on the right of level 2, which when applied to Thinning on the right of level 1 produces intuitionistic out of classical logic (without changing anything else), produces S4 out of S5 (without changing anything else).This characterization of modal constants with sequents of level 2 is unique in the following sense. If constants which differ only graphically are given a formally identical characterization, they can be shown inter-replaceable (not only uniformly) with the original constants salva provability. Customary characterizations of modal constants with sequents of level 1, as well as characterizations in Hilbert-style axiomatizations, are not unique in this sense. This parallels the case with implication, which is not uniquely characterized in Hilbert-style axiomatizations, but can be uniquely characterized with sequents of level 1.These results bear upon theories of philosophical logic which attempt to characterize logical constants syntactically. They also provide an illustration of how alternative logics differ only in their structural rules, whereas their rules for logical constants are identical.

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Localization theorems for matrices and bounds for the zeros of polynomials over quaternion division algebra

Filomat ◽

10.2298/fil1802553a ◽

2018 ◽

Vol 32 (2) ◽

pp. 553-573 ◽

Cited By ~ 2

Author(s):

Sk. Ahmad ◽

Istkhar Ali

Keyword(s):

Zeros Of Polynomials ◽

Sufficient Condition ◽

Complex Matrix ◽

Quaternionic Matrix ◽

Left And Right ◽

The Stability ◽

The Right ◽

Left And Right Eigenvalues ◽

Quaternionic Polynomials

In this paper, we derive Ostrowski and Brauer type theorems for the left and right eigenvalues of a quaternionic matrix. Generalizations of Gerschgorin type theorems are discussed for the left and the right eigenvalues of a quaternionic matrix. After that, a sufficient condition for the stability of a quaternionic matrix is given that generalizes the stability condition for a complex matrix. Finally, a characterization of bounds is derived for the zeros of quaternionic polynomials.

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Genetic analysis of the heterochromatin of chromosome 3 in Drosophila melanogaster. I. Products of compound-autosome detachment.

Genetics ◽

10.1093/genetics/120.2.503 ◽

1988 ◽

Vol 120 (2) ◽

pp. 503-517

Author(s):

G E Marchant ◽

D G Holm

Keyword(s):

Drosophila Melanogaster ◽

Genetic Analysis ◽

Genetic Characterization ◽

Complementation Analysis ◽

Chromosome 3 ◽

Recessive Lethal ◽

The Third ◽

Left And Right ◽

The Right

Abstract The heterochromatin of the third chromosome is the largest uncharacterized region of the Drosophila melanogaster genome, and the last major block of D. melanogaster heterochromatin to be thoroughly analyzed. In the present study, this region was genetically dissected by generating and analyzing a series of attached, detached and reattached third chromosomes. Separate detachment experiments were conducted for all 12 possible combinations of four newly synthesized sister-strand compound-3L and three newly synthesized sister-strand compound-3R chromosomes. A total of 443 recessive lethal detachment products carrying putative heterochromatic deficiencies were tested for complementation in a several-stage complementation analysis. The results revealed the presence of seven separable vital regions in the heterochromatin of chromosome 3. Attempts to reattach deficiency-carrying detachment products established that six of these vital regions are on the left arm, but only one is on the right arm. An analysis of the types and frequencies of detachment-product deficiencies generated in each detachment experiment permitted the genetic characterization of the progenitor compounds. It was also possible to determine the proximal-distal orientation of the genes on each arm, and to identify possible breakpoints for each lethal detachment product produced. The results of this study suggest that vital genes in the heterochromatin of the third chromosome are not randomly distributed between, nor within, the heterochromatic blocks of the left and right arms.

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Further results on Left and Right Generalized Drazin Invertible Operators

Matematychni Studii ◽

10.30970/ms.54.1.98-106 ◽

2020 ◽

Vol 54 (1) ◽

pp. 98-106

Author(s):

So. Messirdi ◽

Sa. Messirdi ◽

B. Messirdi

Keyword(s):

Banach Space ◽

Explicit Formula ◽

Sufficient Conditions ◽

Bounded Operators ◽

Left And Right ◽

The Right ◽

Generalized Drazin Invertible Operators ◽

Jacobson’S Lemma

In this paper we present some new characteristics and expressions of left and right generalized Drazin invertible bounded operators on a Banach space $X.$ An explicit formula relating the left and the right generalized Drazin inverses to spectral idempotents is provided. In addition, we give a characterization of operators in $\mathcal{B}_{l}(X)$ (resp. $\mathcal{B}_{r}(X)$) with equal spectral idempotents, where $\mathcal{B}_{l}(X)$ (resp. $\mathcal{B}_{r}(X)$) denotes the set of all left (resp. right) generalized Drazin invertible bounded operators on $X.$ Next, we give some sufficient conditions which ensure that the product of elements of $\mathcal{B}_{l}(X)$ (resp. $\mathcal{B}_{r}(X)$) remains in $\mathcal{B}_{l}(X)$ (resp. $\mathcal{B}_{r}(X)$). Finally, we extend Jacobson's lemma for left and right generalized Drazin invertibility. The provided results extend certain earlier works given in the literature.

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Comparison of the efficiency of the indexes of Pont and Korkhause with Kernott technique in patients with narrowing of maxilla

Стоматология детского возраста и профилактика ◽

10.33925/1683-3031-2020-20-3-199-203 ◽

2020 ◽

Vol 20 (3) ◽

pp. 199-203

Author(s):

O. I. Admakin ◽

I. A. Solop ◽

A. D. Oksentyuk

Keyword(s):

Dental Treatment ◽

Standard Analysis ◽

Clinical Hospital ◽

Control Models ◽

Diagnostic Models ◽

Left And Right ◽

The Asymmetry ◽

The Right ◽

The University ◽

Medical University

Relevance. The narrowing of the maxilla is one of the most common pathologies in orthodontics. Recent studies show that the narrowing is always asymmetric which is connected to the rotation of the maxilla. To choose the treatment correctly one need a calculation that reveals the asymmetry, which is impossible with using standard indexes.Purpose – to compare efficiency of indexes of Pont and Korkhause with the Kernott's method in patients with narrowing of the maxilla.Materials and methods. The study involved 35 children aged from 8 to 12 years old undergoing dental treatment in the University Children's Clinical Hospital of the First Moscow State Medical University with no comorbidities. For every patient a gypsum model was prepared and after that to carry out the biometrical calculation. In this study two indexes were used: Pont's index and Korkhause's; using this standard analysis the narrowing of the maxilla was revealed. After using Pont's Index and Korkhaus analysis all the models were calculated by the method of Kernott with Kernott's dynamic pentagon.Results. As a result of the analysis of the control diagnostic models a narrowing of the maxilla in 69% of cases (n = 24) was revealed in all cases, the deviation of the size of the dentition was asymmetric. Thus, 65% of the surveyed models showed a narrowing on the right. This narrowing was of a different severity and averaged 15 control models.Conclusions. This shows that for the biometrics of diagnostic models it is necessary to use methods that allow to estimate the width of the dentition rows on the left and on the right separately. To correct the asymmetric narrowing of the dentition, it is preferable to use non-classical expanding devices that act equally on the left and right sides separetly.

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Functional Characterization of the mazEF Toxin-Antitoxin System in the Pathogenic Bacterium Agrobacterium tumefaciens

Microorganisms ◽

10.3390/microorganisms9051107 ◽

2021 ◽

Vol 9 (5) ◽

pp. 1107

Author(s):

Wonho Choi ◽

Yoshihiro Yamaguchi ◽

Ji-Young Park ◽

Sang-Hyun Park ◽

Hyeok-Won Lee ◽

...

Keyword(s):

Agrobacterium Tumefaciens ◽

Physiological Function ◽

Functional Characterization ◽

Site Directed Mutagenesis ◽

In Vitro Assays ◽

Cell Growth Inhibition ◽

The Right

Agrobacterium tumefaciens is a pathogen of various plants which transfers its own DNA (T-DNA) to the host plants. It is used for producing genetically modified plants with this ability. To control T-DNA transfer to the right place, toxin-antitoxin (TA) systems of A. tumefaciens were used to control the target site of transfer without any unintentional targeting. Here, we describe a toxin-antitoxin system, Atu0939 (mazE-at) and Atu0940 (mazF-at), in the chromosome of Agrobacterium tumefaciens. The toxin in the TA system has 33.3% identity and 45.5% similarity with MazF in Escherichia coli. The expression of MazF-at caused cell growth inhibition, while cells with MazF-at co-expressed with MazE-at grew normally. In vivo and in vitro assays revealed that MazF-at inhibited protein synthesis by decreasing the cellular mRNA stability. Moreover, the catalytic residue of MazF-at was determined to be the 24th glutamic acid using site-directed mutagenesis. From the results, we concluded that MazF-at is a type II toxin-antitoxin system and a ribosome-independent endoribonuclease. Here, we characterized a TA system in A. tumefaciens whose understanding might help to find its physiological function and to develop further applications.

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Cloning and Characterization of a Chromosomal Class C β-Lactamase and Its Regulatory Gene in Laribacter hongkongensis

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.49.5.1957-1964.2005 ◽

2005 ◽

Vol 49 (5) ◽

pp. 1957-1964 ◽

Cited By ~ 23

Author(s):

Susanna K. P. Lau ◽

Pak-leung Ho ◽

Maria W. S. Li ◽

Hoi-wah Tsoi ◽

Raymond W. H. Yung ◽

...

Keyword(s):

Genomic Dna ◽

Southern Hybridization ◽

Regulatory Gene ◽

Kinetic Properties ◽

Restriction Fragments ◽

Regulatory Systems ◽

Laribacter Hongkongensis ◽

Consensus Motifs ◽

Class C

ABSTRACT Laribacter hongkongensis, a newly discovered bacterium recently shown to be associated with community-acquired gastroenteritis, is generally resistant to most β-lactams except the carbapenems. We describe the cloning and characterization of a novel chromosomal class C β-lactamase and its regulatory gene in L. hongkongensis. Two genes, ampC and ampR, were cloned by inserting restriction fragments of genomic DNA from L. hongkongensis strain HLHK5 into pBK-CMV to give the recombinant plasmid pBK-LHK-5. The ampR and ampC genes and their promoters were divergently oriented, with the ampR gene immediately upstream of the ampC gene and an intercistronic Lys-R motif, typical of inducible ampC-ampR regulatory systems. The deduced amino acid sequence of the cloned AmpC β-lactamase (pI 8.1) contained consensus motifs characteristic of class C β-lactamases but had identities no greater than 46% to known class C β-lactamases. The kinetic properties of this AmpC were also compatible with those of a class C β-lactamase. PCR of 20 clinical isolates of L. hongkongensis, including HLHK5, showed the presence of both ampC and ampR genes in all isolates. Southern hybridization suggested that the ampC gene of HLHK5 was chromosomally encoded. Subcloning experiments showed that the expression of the ampC gene of HLHK5 was regulated by its ampR gene, which acts as a repressor. The β-lactamase characterized from strain HLHK5 was named LHK-5 (gene, bla LHK-5) and represents the first example of AmpC β-lactamase in the β subdivision of proteobacteria.

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Transcriptomic uniqueness and commonality of the ion channels and transporters in the four heart chambers

Scientific Reports ◽

10.1038/s41598-021-82383-1 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Sanda Iacobas ◽

Bogdan Amuzescu ◽

Dumitru A. Iacobas

Keyword(s):

Ion Channels ◽

Cycle Phase ◽

Functional Roles ◽

Expression Control ◽

Gene Expression Control ◽

Left And Right ◽

The Right ◽

Phase Out ◽

Right Atria ◽

Agilent Microarrays

AbstractMyocardium transcriptomes of left and right atria and ventricles from four adult male C57Bl/6j mice were profiled with Agilent microarrays to identify the differences responsible for the distinct functional roles of the four heart chambers. Female mice were not investigated owing to their transcriptome dependence on the estrous cycle phase. Out of the quantified 16,886 unigenes, 15.76% on the left side and 16.5% on the right side exhibited differential expression between the atrium and the ventricle, while 5.8% of genes were differently expressed between the two atria and only 1.2% between the two ventricles. The study revealed also chamber differences in gene expression control and coordination. We analyzed ion channels and transporters, and genes within the cardiac muscle contraction, oxidative phosphorylation, glycolysis/gluconeogenesis, calcium and adrenergic signaling pathways. Interestingly, while expression of Ank2 oscillates in phase with all 27 quantified binding partners in the left ventricle, the percentage of in-phase oscillating partners of Ank2 is 15% and 37% in the left and right atria and 74% in the right ventricle. The analysis indicated high interventricular synchrony of the ion channels expressions and the substantially lower synchrony between the two atria and between the atrium and the ventricle from the same side.

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