Cloning and molecular analysis of promoter-like sequences isolated from the chromosomal DNA ofLactobacillus acidophilusATCC 4356

1997 ◽  
Vol 43 (1) ◽  
pp. 61-69 ◽  
Author(s):  
G. Djordjevic ◽  
B. Bojovic ◽  
N. Miladinov ◽  
L. Topisirovic
Keyword(s):  
Lactococcus Lactis ◽  
Molecular Analysis ◽  
Lactobacillus Acidophilus ◽  
Promoter Activity ◽  
Lactobacillus Reuteri ◽  
Bacterial Species ◽  
Chromosomal Dna ◽  
Complementary Dna ◽  
E Coli ◽  
Dna Strand

Promoter-like sequences from the chromosomal DNA of thermophilic strain Lactobacillus acidophilus ATCC 4356 were cloned. Analysis of the three DNA fragments showing promoter activity, designated P3, P6, and P15, were performed in Lactobacillus reuteri, Lactococcus lactis, and E. coli. The reporter cat-86 gene was expressed in all three bacterial species under control of the fragments P3 and P6. Fragment P15 showed promoter activity only in Lactobacillus reuteri and E. coli but not in Lactococcus lactis. The three host-specific transcriptional start points (TSPs) were used when transcription of the cat-86 gene was controlled by fragment P3 in Lactobacillus reuteri, E. coli, and Lactococcus lactis. Similarly, fragment P15 initiated transcription of the cat-86 gene at two distinctive sites in Lactobacillus reuteri and E. coli. Only within fragment P6, a common TSP was used in Lactobacillus reuteri and E. coli, but different from that used in Lactococcus lactis. Each TSP was preceded by the putative −35 and −10 hexamers. Computer analysis of the fragment P3 sequence revealed the existence of divergent promoterlike sequence (P3rev) located on the complementary DNA strand. Fragments P6 and P15 were also functional in Lactobacillus acidophilus ATCC 4356 from which chromosomal DNA they were originally cloned.Key words: Lactobacillus acidophilus, promoter-like sequences, regulation.

Molecular analysis of mutatedLactobacillus acidophiluspromoter-like sequence P15

2000 ◽  
Vol 46 (10) ◽  
pp. 938-945 ◽  
Author(s):  
Slavica Arsenijevic ◽  
Ljubisa Topisirovic
Keyword(s):  
Escherichia Coli ◽  
Bacillus Subtilis ◽  
Molecular Analysis ◽  
Lactobacillus Acidophilus ◽  
Promoter Activity ◽  
Lactobacillus Reuteri ◽  
Promoter Sequence ◽  
Chloramphenicol Resistance ◽  
E Coli ◽  
Promoter Probe

The promoter-like sequence P15 that was previously cloned from the chromosome of Lactobacillus acidophilus ATCC 4356 is active in Lactobacillus reuteri, Lactobacillus plantarum, Lactobacillus acidophilus, and Escherichia coli, but not in Lactococcus lactis. N-methyl-N-nitroso-N-guanidine (MNNG) mutagenesis of P15 was used to select for a promoter active in L. lactis MG1363. Molecular analysis of the mutated promoter (designated P16) revealed a 90 bp deletion and a T[Formula: see text]A transversion. This deletion, in combination with the addition to the transversion, created a promoter with putative -35 and -10 hexamers identical to the consensus promoter sequence found in E. coli and Bacillus subtilis vegetative promoters. The activity of P16 was measured by its ability to promote chloramphenicol resistance in different bacteria when inserted in the promoter-probe plasmid pBV5030 (designated pLA16). The MIC of chloramphenicol in L. lactis, L. reuteri, L. plantarum, E. coli, and L. acidophilus harbouring pLA16 were 30, 170, 180, >500, and 3 µg/mL, respectively. This represents an increase in promoter activity compared to P15 in L. reuteri of 3-fold, in L. plantarum of 9-fold, and in E. coli of at least 2.5-fold, but a decrease in L. acidophilus of 7-fold.Key words: Lactobacillus acidophilus, promoter-like sequence, mutagenesis.

Cloning of promoter-like sequences from Lactobacillus paracasei subsp. paracasei CG11 and their expression in Escherichia coli, Lactococcus lactis, and Lactobacillus reuteri

1994 ◽  
Vol 40 (12) ◽  
pp. 1043-1050 ◽  
Author(s):  
Gordana Djordjevic ◽  
Bojana Bojovic ◽  
Ana Banina ◽  
Ljubisa Topisirovic
Keyword(s):  
Escherichia Coli ◽  
Lactococcus Lactis ◽  
Dna Sequences ◽  
Lactobacillus Reuteri ◽  
Lactobacillus Paracasei ◽  
Translational Efficiency ◽  
Broad Host Range ◽  
Chromosomal Dna ◽  
Base Pairs ◽  
E Coli

Fragments of chromosomal DNA from Lactobacillus paracasei subsp. paracasei CG11 (formerly Lactobacillus casei CG11) capable of functioning as promoters were isolated using the broad host range, promoter-probe vector pGKV210. Five such fragments designated P61, P79, P80, P116, and P144 were completely sequenced and analyzed. Fragment P61 had the highest transcriptional efficiency in Escherichia coli and Lactobacillus reuteri whereas P80 was the most active in Lactococcus lactis. In general, the orders of the transcriptional strengths were almost identical in E. coli and Lactobacillus reuteri but different from that in Lactococcus lactis. Mapping of the 5′ end of cat mRNA showed that different regions of fragments P79 and P144 were used as promoters in Lactococcus lactis than in E. coli and Lactobacillus reuteri. Analysis of these DNA sequences revealed that the putative −35 and −10 hexanucleotides resembled those of E. coli, Bacillus subtilis, and lactococci. The spacing between these two hexanucleotides and between the putative −10 hexanucleotide and the transcriptional start point (A residues predominated) ranged from 17 to 18 base pairs and from 5 to 7 base pairs, respectively. Each of the cloned Lactobacillus paracasei CG11 promoter-like fragments contained an AT-rich sequence upstream of the putative −35 region (from 60 to 73%).Key words: Lactobacillus, promoter-like sequences, transcriptional efficiency, translational efficiency.

scholarly journals Evidence for Transfer of CMY-2 AmpC β-Lactamase Plasmids between Escherichia coli andSalmonella Isolates from Food Animals and Humans

2001 ◽  
Vol 45 (10) ◽  
pp. 2716-2722 ◽  
Author(s):  
P. L. Winokur ◽  
D. L. Vonstein ◽  
L. J. Hoffman ◽  
E. K. Uhlenhopp ◽  
G. V. Doern
Keyword(s):  
Escherichia Coli ◽  
Antimicrobial Resistance ◽  
Bacterial Species ◽  
Laboratory Strain ◽  
Epidemiological Studies ◽  
Geographic Region ◽  
Chromosomal Dna ◽  
E Coli ◽  
Clonal Relatedness ◽  
Food Animals

ABSTRACT Escherichia coli is an important pathogen that shows increasing antimicrobial resistance in isolates from both animals and humans. Our laboratory recently described Salmonellaisolates from food animals and humans that expressed an identical plasmid-mediated, AmpC-like β-lactamase, CMY-2. In the present study, 59 of 377 E. coli isolates from cattle and swine (15.6%) and 6 of 1,017 (0.6%) isolates of human E. coli from the same geographic region were resistant to both cephamycins and extended-spectrum cephalosporins. AnampC gene could be amplified with CMY-2 primers in 94.8% of animal and 33% of human isolates. Molecular epidemiological studies of chromosomal DNA revealed little clonal relatedness among the animal and human E. coli isolates harboring the CMY-2 gene. The ampC genes from 10 animal and human E. coli isolates were sequenced, and all carried an identical CMY-2 gene. Additionally, all were able to transfer a plasmid containing the CMY-2 gene to a laboratory strain of E. coli. CMY-2 plasmids demonstrated two different plasmid patterns that each showed strong similarities to previously describedSalmonella CMY-2 plasmids. Additionally, Southern blot analyses using a CMY-2 probe demonstrated conserved fragments among many of the CMY-2 plasmids identified in Salmonella andE. coli isolates from food animals and humans. These data demonstrate that common plasmids have been transferred between animal-associated Salmonella and E. coli, and identical CMY-2 genes carried by similar plasmids have been identified in humans, suggesting that the CMY-2 plasmid has undergone transfer between different bacterial species and may have been transmitted between food animals and humans.

scholarly journals PENGGUNAAN PROBIOTIK KOMBINASI Lactococcus lactis DAN Lactobacillus acidophilus SEBAGAI PENGGANTI ANTIBIOTIKA PADA AYAM PETELUR YANG DIINFEKSI Escherichia coli TERHADAP ANALISIS USAHA

2019 ◽  
Vol 5 (2) ◽  
pp. 183
Author(s):  
Hana Cipka Pramuda Wardhani ◽  
Widya Paramita Lokapirnasari ◽  
Koesnoto Soepranianondo
Keyword(s):  
Escherichia Coli ◽  
Lactococcus Lactis ◽  
Lactobacillus Acidophilus ◽  
Return On Investment ◽  
Egg Production ◽  
Animal Feed ◽  
Payback Period ◽  
Cost Ratio ◽  
E Coli ◽  
A Value

Escherichia coli is a normal flora in the digestive system of laying hens that are non-pathogenic, which can change into pathogens and cause the egg production to decrease. So the combination of Lactococcus lactis and Lactobacillus acidophilus probiotics is expected to be able to overcome E. coli and become a substitute for the  antibiotics (Virginiamycin) in animal feed. This study aims to determine business analysis including Break Event Points (BEP), Revenue Cost Ratio (R / C Ratio), Payback Period (PP) and Return On Investment (ROI). The best results obtained for the calculation of Break Event Point (BEP) on a0b2 treatment with a BEP of Rp. 17,587,24 with BEP production on a1b2 of 14,36 kg, Revenue Cost Ratio (R / C Ratio) generates a value of 1,543 for treatment a0b2, Payback Period (PP) generates a value of 1 year 3 months 9 days and Return On Investment (ROI) generates a value of 3. It was concluded that the a0b2 treatment had good results to be developed.

scholarly journals Molecular Cloning of the fur Gene from Actinobacillus actinomycetemcomitans

2002 ◽  
Vol 70 (6) ◽  
pp. 3170-3179 ◽  
Author(s):  
V. I. Haraszthy ◽  
E. T. Lally ◽  
G. G. Haraszthy ◽  
J. J. Zambon
Keyword(s):  
Gene Product ◽  
Bacterial Species ◽  
Consensus Sequence ◽  
Actinobacillus Actinomycetemcomitans ◽  
Gene Probe ◽  
Virulence Determinants ◽  
Chromosomal Dna ◽  
E Coli ◽  
Therapeutic Modalities ◽  
Serotype B

ABSTRACT In several bacterial species, iron availability in host tissues is coordinated with the expression of virulence determinants through the fur gene product. Initial experiments showed that a cloned Escherichia coli fur gene probe hybridized to Southern blots of Actinobacillus actinomycetemcomitans strain JP2 (serotype b) chromosomal DNA. The A. actinomycetemcomitans fur gene was then cloned utilizing partial functional complementation of the fur mutant in E. coli strain H1780. Analysis of the cloned DNA sequence revealed a 438-bp open reading frame with a deduced 146-amino-acid sequence exhibiting 80% identity to Haemophilus influenzae Fur and 62% identity to E. coli Fur. The pUC Aafur gene probe (generated from JP2 serotype b) hybridized to representatives from all five A. actinomycetemcomitans serotypes as well as to two strains derived from monkeys, suggesting that fur is widely distributed in A. actinomycetemcomitans. Open reading frames having >70% identity with the E. coli and H. influenzae flavodoxin and gyrase A genes, respectively, were found. Expression of the A. actinomycetemcomitans fur gene product repressed fiu expression and siderophore production in E. coli. A gel shift assay demonstrated that the expressed A. actinomycetemcomitans Fur protein bound the bacterial fur consensus sequence. Further characterization of the fur gene product in A. actinomycetemcomitans may improve our understanding of its role in the pathogenesis of periodontal disease and may lead to specific therapeutic modalities.

scholarly journals Identification of Campylobacter jejuniPromoter Sequences

1998 ◽  
Vol 180 (3) ◽  
pp. 594-599 ◽  
Author(s):  
Marc M. S. M. Wösten ◽  
Miranda Boeve ◽  
Mirjam G. A. Koot ◽  
Ad C. van Nuenen ◽  
Bernard A. M. van der Zeijst
Keyword(s):  
Campylobacter Jejuni ◽  
Promoter Activity ◽  
Shuttle Vector ◽  
Consensus Sequence ◽  
Chromosomal Dna ◽  
Strong Promoter ◽  
E Coli ◽  
Gram Positive Bacteria ◽  
Transcriptional Start Point ◽  
Transcriptional Start Sites

ABSTRACT A promoterless lacZ shuttle vector, which allowed screening of promoters by β-galactosidase activity inCampylobacter jejuni and Escherichia coli, was developed. Chromosomal DNA fragments from C. jejuniwere cloned into this vector; 125 of 1,824 clones displayed promoter activity in C. jejuni. Eleven clones with strong promoter activity in C. jejuni were further characterized. Their nucleotide sequences were determined, and the transcriptional start sites of the putative promoters in C. jejuni were determined by primer extension. Only 6 of these 11 promoters were functional in E. coli. The 11 newly characterized and 10 previously characterized C. jejuni promoters were used to establish a consensus sequence for C. jejuni promoters. The 21 promoters were found to be very similar. They contain three conserved regions, located approximately 10, 16, and 35 bp upstream of the transcriptional start point. The −10 region resembles that of a typical ς70 E. colipromoter, but the −35 region is completely different. In addition a −16 region typical for gram-positive bacteria was identified.

scholarly journals Occurrence of Homologs of the Escherichia coli lytB Gene in Gram-Negative Bacterial Species

1998 ◽  
Vol 180 (7) ◽  
pp. 1959-1961 ◽  
Author(s):  
Sheila Potter ◽  
Xiaoming Yang ◽  
Martin J. Boulanger ◽  
Edward E. Ishiguro
Keyword(s):  
Escherichia Coli ◽  
Southern Blot ◽  
Blot Analysis ◽  
Southern Blot Analysis ◽  
Mutant Allele ◽  
Bacterial Species ◽  
Enterobacter Aerogenes ◽  
Chromosomal Dna ◽  
Gram Negative ◽  
E Coli

ABSTRACT The Escherichia coli LytB protein regulates the activity of guanosine 3′,5′-bispyrophosphate synthetase I (RelA). A Southern blot analysis of chromosomal DNA with the E. coli lytB gene as a probe revealed the presence of lytBhomologs in all of the gram-negative bacterial species examined but not in gram-positive species. The lytB homologs fromEnterobacter aerogenes and Pseudomonas fluorescens complemented the E. coli lytB44 mutant allele.

Efficacy of Silver Nanoparticles Synthesized from Hymenocallis species (Spider Lilly) Leaf Extract as Antimicrobial Agents

2019 ◽  
Vol 12 (5) ◽  
pp. 4644-4647
Author(s):  
K.K. Gupta ◽  
Neha Kumari ◽  
Neha Sinha ◽  
Akruti Gupta
Keyword(s):  
Silver Nanoparticles ◽  
Leaf Extract ◽  
Antimicrobial Agents ◽  
Color Change ◽  
Bacterial Species ◽  
Antimicrobial Property ◽  
Biogenic Synthesis ◽  
E Coli ◽  
Light Yellow ◽  
Antibiotic Property

Biogenic synthesis of silver nanoparticles synthesized from Hymenocallis species (Spider Lilly) leaf extract was subjected for investigation of its antimicrobial property against four bacterial species (E. coli, Salmonella sp., Streptococcus sp. & Staphylococcus sp.). The results revealed that synthesized nanoparticles solution very much justify the color change property from initial light yellow to final reddish brown during the synthesis producing a characteristics absorption peak in the range of 434-466 nm. As antimicrobial agents, their efficacy was evaluated by analysis of variance in between the species and among the different concentration of AgNPs solution, which clearly showed that there was significant variation in the antibiotic property between the four different concentrations of AgNPs solution and also among four different species of bacteria taken under studies. However, silver nanoparticles solution of 1: 9 and 1:4 were proved comparatively more efficient as antimicrobial agents against four species of bacteria.

Substituted 6,7-dimethoxy-5-oxo-2,3,5,9b-tetrahydrothiazolo[2,3-a]isoindole- 3-1,1-dioxide Derivatives with Antimicrobial Activity and Docking Assisted Prediction of the Mechanism of their Antibacterial and Antifungal Properties

2020 ◽  
Vol 20 (29) ◽  
pp. 2681-2691
Author(s):  
Athina Geronikaki ◽  
Victor Kartsev ◽  
Phaedra Eleftheriou ◽  
Anthi Petrou ◽  
Jasmina Glamočlija ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Antifungal Activity ◽  
Drug Targets ◽  
Bacterial Species ◽  
Pharmaceutical Research ◽  
Docking Studies ◽  
Fungal Species ◽  
Docking Analysis ◽  
E Coli ◽  
Antibacterial And Antifungal

Background: Although a great number of the targets of antimicrobial therapy have been achieved, it remains among the first fields of pharmaceutical research, mainly because of the development of resistant strains. Docking analysis may be an important tool in the research for the development of more effective agents against specific drug targets or multi-target agents 1-3. Methods: In the present study, based on docking analysis, ten tetrahydrothiazolo[2,3-a]isoindole derivatives were chosen for the evaluation of the antimicrobial activity. Results: All compounds showed antibacterial activity against eight Gram-positive and Gram-negative bacterial species being, in some cases, more potent than ampicillin and streptomycin against all species. The most sensitive bacteria appeared to be S. aureus and En. Cloacae, while M. flavus, E. coli and P. aeruginosa were the most resistant ones. The compounds were also tested for their antifungal activity against eight fungal species. All compounds exhibited good antifungal activity better than reference drugs bifonazole (1.4 – 41 folds) and ketoconazole (1.1 – 406 folds) against all fungal species. In order to elucidate the mechanism of action, docking studies on different antimicrobial targets were performed. Conclusion: According to docking analysis, the antifungal activity can be explained by the inhibition of the CYP51 enzyme for most compounds with a better correlation of the results obtained for the P.v.c. strain (linear regression between estimated binding Energy and log(1/MIC) with R 2 =0.867 and p=0.000091 or R 2 = 0.924, p= 0.000036, when compound 3 is excluded.

scholarly journals Evolution of Chi motifs in Proteobacteria

2021 ◽  
Author(s):  
Angélique Buton ◽  
Louis-Marie Bobay
Keyword(s):  
Sequence Similarity ◽  
Bacterial Species ◽  
Double Strand Breaks ◽  
Dna Double Strand Breaks ◽  
Large Dataset ◽  
High Sequence Similarity ◽  
Strand Breaks ◽  
E Coli ◽  
Dna Motif ◽  
And Staphylococcus Aureus

Abstract Homologous recombination is a key pathway found in nearly all bacterial taxa. The recombination complex allows bacteria to repair DNA double strand breaks but also promotes adaption through the exchange of DNA between cells. In Proteobacteria, this process is mediated by the RecBCD complex, which relies on the recognition of a DNA motif named Chi to initiate recombination. The Chi motif has been characterized in Escherichia coli and analogous sequences have been found in several other species from diverse families, suggesting that this mode of action is widespread across bacteria. However, the sequences of Chi-like motifs are known for only five bacterial species: E. coli, Haemophilus influenzae, Bacillus subtilis, Lactococcus lactis and Staphylococcus aureus. In this study we detected putative Chi motifs in a large dataset of Proteobacteria and we identified four additional motifs sharing high sequence similarity and similar properties to the Chi motif of E. coli in 85 species of Proteobacteria. Most Chi motifs were detected in Enterobacteriaceae and this motif appears well conserved in this family. However, we did not detect Chi motifs for the majority of Proteobacteria, suggesting that different motifs are used in these species. Altogether these results substantially expand our knowledge on the evolution of Chi motifs and on the recombination process in bacteria.

Sign in / Sign up

Export Citation Format

Share Document