ABSTRACT The microbiota of the intestinal tract chickens plays an important role in inhibiting establishment pathogens. Earlier culturing and microscopic examinations indicated that only a fraction bacteria cecum could be grown laboratory. Therefore, survey cecal was done by retrieval 16S rRNA gene sequences from DNA isolated content mucosa. ribosomal were amplified with universal primers cloned or subjected to temporal temperature gradient gel electrophoresis (TTGE). Partial determined...

Abstract A tremendous effort has been made over the last decade to develop and test films with antimicrobial properties improve food safety shelf life. This review catalogues analyses outcome of these research efforts. The bacteriocin nisin was most commonly incorporated into films, followed by food‐grade acids salts, chitosan, plant extracts, enzymes lysozyme lactoperoxidase. methodologies for measuring activity both edible inedible varied considerably among studies. Results, defined as...

Considerable controversy exists regarding the exact nature of molecular mechanism interfacial activation, a process by which most lipases achieve maximum catalytic activity upon adsorption to an oil water interface.X-ray crystallographic studies show that contain buried active centers and displacements entire secondary structure elements, or "lids,'' take place when enzymes assume conformations [Derewenda, U., A.

A 3.8-kilobase-pair EcoRI fragment which corrects the mutations carried by NifB- Azotobacter vinelandii strains CA30 and UW45 was cloned, its nucleotide sequence determined. Four complete open reading frames (ORFs) two partial ORFs were found. The translation product of first ORF is carboxy-terminal end a protein homologous to nifA gene from Klebsiella pneumoniae. 285-base-pair containing potential nif promoter regulatory sites separates this encodes nifB products K. pneumoniae Rhizobium...

The nucleotide sequence of a region the Azotobacter vinelandii genome exhibiting similarity to nifH has been determined. order open reading frames within this 6.1-kilobase-pair was found be anfH (alternative nitrogen fixation, nifH-like gene), anfD (nifD-like anfG (potentially encoding protein similar product vnfG from chroococcum), anfK (nifK-like followed by two additional frames. 5'-flanking contains nif promoter that in A. nifHDK gene cluster. presumed products anfH, anfD, and are...

A multianalyte immunoassay for simultaneous detection of three analytes (hTSH, hCG and beta-Gal) has been demonstrated using DNA-labeled antibodies polymerase chain reaction (PCR) amplification assay response. The labeled were prepared by covalently coupling uniquely designed DNA oligonucleotides to each the analyte-specific monoclonal antibodies. Each oligonucleotide labels contained same primer sequences facilitate co-amplification a single pair. Assays performed two-antibody sandwich...

Crop loss due to soil salinization is an increasing threat agriculture worldwide. This review provides overview of cellular and physiological mechanisms in plant responses salt. We place a time- tissue-dependent context ...Read More

The nucleotide sequence (6,559 base pairs) of the genomic region containing structural genes for nitrogenase 2 (V nitrogenase) from Azotobacter vinelandii was determined. open reading frames present in this are organized into two transcriptional units. One contains vnfH (encoding dinitrogenase reductase 2) and a ferredoxinlike frame (Fd). second one includes vnfD alpha subunit 2), vnfG product similar to delta A. chroococcum), vnfK beta 2). 5'-flanking regions contain sequences...

Scutellaria baicalensis Georgi (SBG), commonly named Huangqin, showed strong in vitro antimicrobial effects. However, limited research is available to systematically evaluate the effects of extraction methods on phytochemical composition SBG and its associated In addition, studies have tested as a natural agent fresh produce such tomatoes. current study, powered roots were extracted with 60, 80, 100% ethanol, their antiviral antibacterial activities evaluated. ethanol extracts (SBGEEs) at...

ABSTRACT Bacteriophage capable of lysing a nalidixic acid‐resistant Salmonella enterica serovar Enteritidis strain (Se E Nal r ) were tested for the ability to reduce cecal counts in young chickens infected with bacterium. Qualitative analysis cloacal swabs suggested that phage treatment can possibly shedding Se , but average between 10 5 and 7 cfu per g cecum obtained even from phage‐treated 14‐day old birds when more than plaque forming units present gram content. The generally 0.3 1.3...

A polymerase chain reaction (PCR)-based detection system, BAX, was evaluated for its sensitivity in detecting Salmonella Enteritidis, Escherichia coli O157:H7, Listeria sp., and monocytogenes on fresh produce. Fifteen different types of produce (alfalfa sprouts, green peppers, parsley, white cabbage, radishes, onions, carrots, mushrooms, leaf lettuce, tomatoes, strawberries, cantaloupe, mango, apples, oranges) were inoculated, separate studies, with E. L. down to the predicted level 1 CFU...

Two nifA-like genes, designated anfA and vnfA, have been identified in Azotobacter vinelandii. The gene is located upstream from the nitrogenase-3 structural cluster (anfHDGK) preceded by a sequence that potentially part of ntrA-dependent promoter. product appears to be required for expression nitrogenase-3, since cells deletion strain CA66 were unable synthesize this nitrogenase when derepressed N-free, Mo- V-deficient medium. vnfA was after determination nucleotide DNA flanking Tn5...

Journal Article Current progress, in crystallographic studies of new Upases from filamentous fungi Get access U. Derewenda, Derewenda Search for other works by this author on: Oxford Academic PubMed Google Scholar L. Swenson, Swenson R. Green, Green Y. Wei, Wei S. Yamaguchi, Yamaguchi 1Tsukuba Research Laboratories, Amano Pharmaceutical Co. LtdTsukuba, Japan Joerger, Joerger 2US Department Agriculture, Agricultural Service, North Atlantic Area Eastern Regional CenterPhiladelphia, USA M. J....

We demonstrate immuno-polymerase chain reaction (PCR) assays for two clinical analytes--human thyroid-stimulating hormone and chorionic gonadotropin (hTSH, hCG)--using DNA-labeled antibodies PCR amplification of assay response. DNA-antibody conjugates were synthesized by using heterobifunctional cross-linker chemistries to covalently attach single- or double-stranded DNA labels through amine sulfhydryl groups on the analyte antibodies. These approaches yielded molecular chimeras possessing...

Abstract The coding sequences of the Rhizopus delemar lipase and prolipase were altered by oligonucleotide‐directed mutagenesis to introduce amino acid substitutions. resulting mutant enzymes, synthesized bacterial host Escherichia coli BL21 (DE3), tested for their ability hydrolyze triglycerides triolein (TO), tricaprylin (TC) tributyrin (TB). Mutagenesis gene expression carried out using plasmid vectors derived from previously described recombinant plasmids [Joerger Haas (1993) Lipids 28 ,...

Agrobacterium tumefaciens initiates the expression of pathogenic genes (vir genes) in response to host-derived phenolic signals through a two-component regulatory system consisting VirA and VirG. alpha-Bromoacetosyringone (ASBr) was developed as an inhibitor this induction process found be specific irreversible vir gene pathogen. Formal replacement one methoxy groups ASBr with iodine gave equally effective that could carry 125I label. We report here resulting radiolabeled does not react...

The aglycone of the dihydrodiconiferyl alcohol glycosides, a series phenolic growth factors able to substitute for some hormone requirements tobacco cell division, are also potent inducers virulence gene expression in Agrobacterium tumefaciens. However, these do not conform previously established structural necessary vir expression. Systematic evaluation has led model detailing role phenolics induction. With this model, specific inhibitor induction been developed. This does affect other...

Mutants of Azotobacter vinelandii affected in N2 fixation the presence 1 microM Na2MoO4 (conventional system), 50 nM V2O5, or under Mo deficiency (alternative system) have been isolated after Tn5 mutagenesis with suicide plasmid pSUP1011. These mutants can be grouped into at least four broad phenotypic classes. first class are Nif- sufficiency but Nif+ V2O5. A nifk mutant and a apparently regulation conventional system belong to this class. second all conditions. An FeMo-cofactor-negative...

Abstract Ethylene copolymer film was coated with chitosan by attachment of the polymer to corona‐treated surface film, and composite analysed for antimicrobial activity. The active against bacteria in 0.625 mM phosphate buffer; it reduced colony counts Escherichia coli 25922 Listeria monocytogenes Scott A 5 2–3 log 10 , respectively after 24 h exposure. activity chitosan‐coated buffer increased when silver ions were incorporated into films as demonstrated complete killing O157:H7 DD3795...