scholarly journals Identification of a nisI Promoter within the nisABCTIP Operon That May Enable Establishment of Nisin Immunity Prior to Induction of the Operon via Signal Transduction

2006 ◽  
Vol 188 (24) ◽  
pp. 8496-8503 ◽  
Author(s):  
Haiping Li ◽  
Daniel J. O'Sullivan
Keyword(s):  
Transcription Initiation ◽  
Start Codon ◽  
Northern Analysis ◽  
Pcr Analysis ◽  
Translation Start ◽  
Promoter Probe ◽  
Genes Encoding ◽  
Promoter Probe Vector ◽  
Successful Establishment ◽  
High Degree

ABSTRACT Certain strains of Lactococcus lactis produce the broad-spectrum bacteriocin nisin, which belongs to the lantibiotic class of antimicrobial peptides. The genes encoding nisin are organized in three contiguous operons: nisABTCIP, encoding production and immunity (nisI); nisRK, encoding regulation; and nisFEG, also involved in immunity. Transcription of nisABTCIP and nisFEG requires autoinduction by external nisin via signal transducing by NisRK. This organization poses the intriguing question of how sufficient immunity (NisI) can be expressed when the nisin cluster enters a new cell, before it encounters external nisin. In this study, Northern analysis in both Lactococcus and Enterococcus backgrounds revealed that nisI mRNA was present under conditions when no nisA transcription was occurring, suggesting an internal promoter within the operon. The nisA transcript was significantly more stable than nisI, further substantiating this. Reverse transcriptase PCR analysis revealed that the transcription initiated just upstream from nisI. Fusing this region to a lacZ gene in a promoter probe vector demonstrated that a promoter was present. The transcription start site (TSS) of the nisI promoter was mapped at bp 123 upstream of the nisI translation start codon. Ordered 5′ deletions revealed that transcription activation depended on sequences located up to bp −234 from the TSS. The presence of poly(A) tracts and computerized predictions for this region suggested that a high degree of curvature may be required for transcription initiation. The existence of this nisI promoter is likely an evolutionary adaptation of the nisin gene cluster to enable its successful establishment in other cells following horizontal transfer.

Analysis of the promoter activities of the genes encoding three quinoprotein alcohol dehydrogenases in Pseudomonas putida HK5

Microbiology ◽  
2009 ◽  
Vol 155 (2) ◽  
pp. 594-603 ◽  
Author(s):  
Worrawat Promden ◽  
Alisa S. Vangnai ◽  
Hirohide Toyama ◽  
Kazunobu Matsushita ◽  
Piamsook Pongsawasdi
Keyword(s):  
Transcriptional Regulation ◽  
Pseudomonas Putida ◽  
Regulatory Network ◽  
Alcohol Oxidation ◽  
Gene Products ◽  
Response Regulators ◽  
Divergent Promoters ◽  
Promoter Probe ◽  
Genes Encoding ◽  
Promoter Probe Vector

The transcriptional regulation of three distinct alcohol oxidation systems, alcohol dehydrogenase (ADH)-I, ADH-IIB and ADH-IIG, in Pseudomonas putida HK5 was investigated under various induction conditions. The promoter activities of the genes involved in alcohol oxidation were determined using a transcriptional lacZ fusion promoter-probe vector. Ethanol was the best inducer for the divergent promoters of qedA and qedC, encoding ADH-I and a cytochrome c, respectively. Primary and secondary C3 and C4 alcohols and butyraldehyde specifically induced the divergent promoters of qbdBA and aldA, encoding ADH-IIB and an NAD-dependent aldehyde dehydrogenase, respectively. The qgdA promoter of ADH-IIG responded well to (S)-(+)-1,2-propanediol induction. In addition, the roles of genes encoding the response regulators exaE and agmR, located downstream of qedA, were inferred from the properties of exaE- or agmR-disrupted mutants and gene complementation tests. The gene products of both exaE and agmR were strictly necessary for qedA transcription. The mutation and complementation studies also suggested a role for AgmR, but not ExaE, in the transcriptional regulation of qbdBA (ADH-IIB) and qgdA (AGH-IIG). A hypothetical scheme describing a regulatory network, which directs expression of the three distinct alcohol oxidation systems in P. putida HK5, was derived.

scholarly journals The groESL Chaperone Operon ofLactobacillus johnsonii

1999 ◽  
Vol 65 (7) ◽  
pp. 3033-3041 ◽  
Author(s):  
D. Carey Walker ◽  
Hany S. Girgis ◽  
Todd R. Klaenhammer
Keyword(s):  
Heat Shock ◽  
Transcription Initiation ◽  
Shuttle Vector ◽  
Stress Protein ◽  
Open Reading Frames ◽  
Northern Analysis ◽  
Temperature Sensitive ◽  
Insertion Element ◽  
Translation Start ◽  
Reading Frames

ABSTRACT The Lactobacillus johnsonii VPI 11088groESL operon was localized on the chromosome near the insertion element IS1223. The operon was initially cloned as a series of three overlapping PCR fragments, which were sequenced and used to design primers to amplify the entire operon. The amplified fragment was used as a probe to recover the chromosomal copy of thegroESL operon from a partial library of L. johnsonii VPI 11088 (NCK88) DNA, cloned in the shuttle vector pTRKH2. The 2,253-bp groESL fragment contained three putative open reading frames, two of which encoded the ubiquitous GroES and GroEL chaperone proteins. Analysis of the groESLpromoter region revealed three transcription initiation sites, as well as three sets of inverted repeats (IR) positioned between the transcription and translation start sites. Two of the three IR sets bore significant homology to the CIRCE elements, implicated in negative regulation of the heat shock response in many bacteria. Northern analysis and primer extension revealed that multiple temperature-sensitive promoters preceded the groESLchaperone operon, suggesting that stress protein production in L. johnsonii is strongly regulated. Maximum groESLtranscription activity was observed following a shift to 55°C, and a 15 to 30-min exposure of log-phase cells to this temperature increased the recovery of freeze-thawed L. johnsonii VPI 11088. These results suggest that a brief, preconditioning heat shock can be used to trigger increased chaperone production and provide significant cross-protection from the stresses imposed during the production of frozen culture concentrates.

scholarly journals Roles of Si and SiNPs in Improving Thermotolerance of Wheat Photosynthetic Machinery via Upregulation of PsbH, PsbB and PsbD Genes Encoding PSII Core Proteins

Horticulturae ◽  
2021 ◽  
Vol 7 (2) ◽  
pp. 16
Author(s):  
Heba Hassan ◽  
Aishah Alatawi ◽  
Awatif Abdulmajeed ◽  
Manal Emam ◽  
Hemmat Khattab
Keyword(s):  
Photosystem Ii ◽  
Global Climate ◽  
Soluble Sugars ◽  
Triticum Aestivum L ◽  
Pcr Analysis ◽  
Silicon Dioxide Nanoparticles ◽  
System Productivity ◽  
Photosynthetic System ◽  
Core Proteins ◽  
Genes Encoding

Photosystem II is extremely susceptible to environmental alterations, particularly high temperatures. The maintenance of an efficient photosynthetic system under stress conditions is one of the main issues for plants to attain their required energy. Nowadays, searching for stress alleviators is the main goal for maintaining photosynthetic system productivity and, thereby, crop yield under global climate change. Potassium silicate (K2SiO3, 1.5 mM) and silicon dioxide nanoparticles (SiO2NPs, 1.66 mM) were used to mitigate the negative impacts of heat stress (45 °C, 5 h) on wheat (Triticum aestivum L.) cv. (Shandawelly) seedlings. The results showed that K2SiO3 and SiO2NPs diminished leaf rolling symptoms and electrolyte leakage (EL) of heat-stressed wheat leaves. Furthermore, the maximum quantum yield of photosystem II (Fv/Fm) and the performance index (PIabs), as well as the photosynthetic pigments and organic solutes including soluble sugars, sucrose, and proline accumulation, were increased in K2SiO3 and SiO2NPs stressed leaves. At the molecular level, RT-PCR analysis showed that K2SiO3 and SiO2NPs treatments stimulated the overexpression of PsbH, PsbB, and PsbD genes. Notably, this investigation indicated that K2SiO3 was more effective in improving wheat thermotolerance compared to SiO2NPs. The application of K2SiO3 and SiO2NPs may be one of the proposed approaches to improve crop growth and productivity to tolerate climatic change.

scholarly journals Essential and nonessential histone H2A variants in Tetrahymena thermophila.

1996 ◽  
Vol 16 (8) ◽  
pp. 4305-4311 ◽  
Author(s):  
X Liu ◽  
B Li ◽  
GorovskyMA
Keyword(s):  
Tetrahymena Thermophila ◽  
Essential Gene ◽  
Histone Variants ◽  
Gene Replacement ◽  
Histone H2a ◽  
Gene Encoding ◽  
Genes Encoding ◽  
Simple Mass ◽  
Essential Function ◽  
High Degree

Although variants have been identified for every class of histone, their functions remain unknown. We have been studying the histone H2A variant hv1 in the ciliated protozoan Tetrahymena thermophila. Sequence analysis indicates that hv1 belongs to the H2A.F/Z type of histone variants. On the basis of the high degree of evolutionary conservation of this class of histones, they are proposed to have one or more distinct and essential functions that cannot be performed by their major H2A counterparts. Considerable evidence supports the hypothesis that the hv1 protein in T. thermophila and hv1-like proteins in other eukaryotes are associated with active chromatin. In T. thermophila, simple mass transformation and gene replacement techniques have recently become available. In this report, we demonstrate that either the HTA1 gene or the HTA2 gene, encoding the major H2As, can be completely replaced by disrupted genes in the polyploid, transcriptionally active macronucleus, indicating that neither of the two genes is essential. However, only some of the HTA3 genes encoding hv1 can be replaced by disrupted genes, indicating that the H2A.F/Z type variants have an essential function that cannot be performed by the major H2A genes. Thus, an essential gene in T. thermophila can be defined by the fact that it can be partially, but not completely, eliminated from the polyploid macronucleus. To our knowledge, this study represents the first use of gene disruption technology to study core histone gene function in any organism other than yeast and the first demonstration of an essential gene in T. thermophila using these methods. When a rescuing plasmid carrying a wild-type HTA3 gene was introduced into the T. thermophila cells, the endogenous chromosomal HTA3 could be completely replaced, defining a gene replacement strategy that can be used to analyze the function of essential genes.

Molecular cloning, sequencing, and chromosome mapping of a 1A-encoded ω-type prolamin sequence from wheat

Genome ◽  
2002 ◽  
Vol 45 (4) ◽  
pp. 661-669 ◽  
Author(s):  
Ali Masoudi-Nejad ◽  
Shuhei Nasuda ◽  
Akira Kawabe ◽  
Takashi R Endo
Keyword(s):  
Storage Proteins ◽  
Protein Structures ◽  
Seed Storage ◽  
Chromosome Mapping ◽  
Seed Storage Proteins ◽  
Gene Families ◽  
Start Codon ◽  
Pcr Analysis ◽  
Bread Making ◽  
Deletion Lines

Gliadins are the most abundant component of the seed storage proteins in cereals and, in combination with glutenins, are important for the bread-making quality of wheat. They are divided into four subfamilies, the α-, β-, γ-, and ω-gliadins, depending on their electrophoresis pattern, chromosomal location, and DNA and protein structures. Using a PCR-based strategy we isolated and sequenced an ω-gliadin sequence. We also determined the chromosomal subarm location of this sequence using wheat aneuploids and deletion lines. The gene is 1858 bp long and contains a coding sequence 1248 bp in length. Like all other gliadin gene families characterized in cereals, the ω-gliadin gene described here had characteristic features including two repeated sequences 300 bp upstream of the start codon. At the DNA level, the gene had a high degree of similarity to the ω-secalin and C-hordein genes of rye and barley, but exhibited much less homology to the α- and β-gliadin gene families. In terms of the deduced amino acid sequence, this gene has about 80 and 70% similarity to the ω-secalin and C-hordein genes, respectively, and possesses all the features reported for other gliadin gene families. The ω-gliadin gene has about 30 repeats of the core consensus sequences PQQPX and XQQPQQX, twice as many as other gliadin gene families. Southern blotting and PCR analysis with aneuploid and deletion lines for the short arm of chromosome 1A showed that the ω-gliadin was located on the distal 25% of the short arm of chromosome 1A. By comparison of PCR and A-PAGE profiles for deletion stocks, its genomic location must be at a different locus from gli-A1a in 'Chinese Spring'.Key words: glutenin, omega gliadin, storage protein, Triticum aestivum, secalin.

scholarly journals Differential Expression of Pine and Cronartium quercuum f. sp. fusiforme Genes in Fusiform Rust Galls

2004 ◽  
Vol 70 (1) ◽  
pp. 441-451 ◽  
Author(s):  
Jaimie M. Warren ◽  
Sarah F. Covert
Keyword(s):  
Stress Responses ◽  
Axenic Culture ◽  
The United States ◽  
Northern Analysis ◽  
Pcr Analysis ◽  
Rust Disease ◽  
Fusiform Rust ◽  
Expression Levels ◽  
Cronartium Quercuum ◽  
Gene Expression Levels

ABSTRACT Cronartium quercuum f. sp. fusiforme is the causative agent of fusiform rust disease of southern pines in the United States. This disease is characterized by the formation of woody branch and stem galls. Differential display was used to identify pine genes whose expression is altered by C. quercuum f. sp. fusiforme infection and to identify C. quercuum f. sp. fusiforme genes that are expressed in fusiform rust galls. Six pine cDNAs that appeared to be differentially expressed in galled and healthy stems and 13 C. quercuum f. sp. fusiforme cDNAs expressed in galled tissues were identified. A probe that hybridizes specifically to C. quercuum f. sp. fusiforme 18S rRNA was used to estimate that 14% of the total RNA in fusiform rust galls was from C. quercuum f. sp. fusiforme. This finding was used to calibrate gene expression levels in galls when comparing them to expression levels in uninfected pines or in isolated C. quercuum f. sp. fusiforme cultures. According to Northern analysis and reverse transcriptase PCR analysis, all six of the pine clones were expressed at lower levels in galls than in healthy tissues. Seven of the nine C. quercuum f. sp. fusiforme clones that were assayed were expressed at higher levels in galls than in axenic culture. A number of the cDNAs encode proteins that are similar to those that play roles in plant development, plant defense, or fungal stress responses.

scholarly journals Transcriptional analysis of the F0F1 ATPase operon of Corynebacterium glutamicum ATCC 13032 reveals strong induction by alkaline pH

Microbiology ◽  
2006 ◽  
Vol 152 (1) ◽  
pp. 11-21 ◽  
Author(s):  
Mónica Barriuso-Iglesias ◽  
Carlos Barreiro ◽  
Fabio Flechoso ◽  
Juan F. Martín
Keyword(s):  
Corynebacterium Glutamicum ◽  
Consensus Sequence ◽  
Transcriptional Analysis ◽  
Alkaline Ph ◽  
Promoter Regions ◽  
Stress Response Genes ◽  
Promoter Probe ◽  
Promoter Probe Vector ◽  
Reduced Rate ◽  
Extension Analysis

Corynebacterium glutamicum, a soil Gram-positive bacterium used for industrial amino acid production, was found to grow optimally at pH 7·0–9·0 when incubated in 5 litre fermenters under pH-controlled conditions. The highest biomass was accumulated at pH 9·0. Growth still occurred at pH 9·5 but at a reduced rate. The expression of the pH-regulated F0F1 ATPase operon (containing the eight genes atpBEFHAGDC) was induced at alkaline pH. A 7·5 kb transcript, corresponding to the eight-gene operon, was optimally expressed at pH 9·0. The same occurred with a 1·2 kb transcript corresponding to the atpB gene. RT-PCR studies confirmed the alkaline pH induction of the F0F1 operon and the existence of the atpI gene. The atpI gene, located upstream of the F0F1 operon, was expressed at a lower level than the polycistronic 7·5 kb mRNA, from a separate promoter (P-atp1). Expression of the major promoter of the F0F1 operon, designated P-atp2, and the P-atp1 promoter was quantified by coupling them to the pET2 promoter-probe vector. Both P-atp1 and P-atp2 were functional in C. glutamicum and Escherichia coli. Primer extension analysis identified one transcription start point inside each of the two promoter regions. The P-atp1 promoter fitted the consensus sequence of promoters recognized by the vegetative σ factor of C. glutamicum, whereas the −35 and −10 boxes of P-atp2 fitted the consensus sequence for σ H-recognized Mycobacterium tuberculosis promoters CC/GGGA/GAC 17–22 nt C/GGTTC/G, known to be involved in expression of heat-shock and other stress-response genes. These results suggest that the F0F1 operon is highly expressed at alkaline pH, probably using a σ H RNA polymerase.

scholarly journals Nitrous oxide production and consumption: regulation of gene expression by gas-sensitive transcription factors

2012 ◽  
Vol 367 (1593) ◽  
pp. 1213-1225 ◽  
Author(s):  
Stephen Spiro
Keyword(s):  
Nitrous Oxide ◽  
Transcription Initiation ◽  
Regulatory Networks ◽  
Regulation Of Gene Expression ◽  
Environmental Signals ◽  
Production And Consumption ◽  
Genes Encoding ◽  
Nitrous Oxide Production ◽  
Biochemical Mechanisms ◽  
Nitrate And Nitrite

Several biochemical mechanisms contribute to the biological generation of nitrous oxide (N 2 O). N 2 O generating enzymes include the respiratory nitric oxide (NO) reductase, an enzyme from the flavo-diiron family, and flavohaemoglobin. On the other hand, there is only one enzyme that is known to use N 2 O as a substrate, which is the respiratory N 2 O reductase typically found in bacteria capable of denitrification (the respiratory reduction of nitrate and nitrite to dinitrogen). This article will briefly review the properties of the enzymes that make and consume N 2 O, together with the accessory proteins that have roles in the assembly and maturation of those enzymes. The expression of the genes encoding the enzymes that produce and consume N 2 O is regulated by environmental signals (typically oxygen and NO) acting through regulatory proteins, which, either directly or indirectly, control the frequency of transcription initiation. The roles and mechanisms of these proteins, and the structures of the regulatory networks in which they participate will also be reviewed.

scholarly journals Analogs of Eap Protein Are Conserved and Prevalent in Clinical Staphylococcus aureus Isolates

2001 ◽  
Vol 8 (6) ◽  
pp. 1271-1276 ◽  
Author(s):  
Muzaffar Hussain ◽  
Karsten Becker ◽  
Christof von Eiff ◽  
Georg Peters ◽  
Mathias Herrmann
Keyword(s):  
Staphylococcus Aureus ◽  
Extracellular Matrix ◽  
Staphylococcus Epidermidis ◽  
Translation Termination ◽  
Pcr Analysis ◽  
Cloning And Sequencing ◽  
Extracellular Matrix Molecules ◽  
Size Variability ◽  
Early Translation ◽  
High Degree

ABSTRACT Map and Eap are secreted Staphylococcus aureus proteins that interact with various extracellular matrix molecules. PCR analysis using map primers yielded positive reactions in 97.9% of S. aureus isolates but not in Staphylococcus epidermidis isolates. Cloning and sequencing of the conferring genes revealed a high degree of overall homology combined with size variability of the gene product due to various repeat numbers and early translation termination in a poly(A) region. Thus, Map and Eap may provide a potential novel tool forS. aureus identification and typing.

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