Genetic analysis of Aspergillus nidulans unstable transformants obtained by the biolistic process

1998 ◽  
Vol 44 (12) ◽  
pp. 1137-1141 ◽  
Author(s):  
Fernando Gomes Barcellos ◽  
Maria Helena Pelegrinelli Fungaro ◽  
Márcia Cristina Furlaneto ◽  
Bernard Lejeune ◽  
Aline A Pizzirani-Kleiner ◽  
...  
Keyword(s):  
Genetic Analysis ◽  
Aspergillus Nidulans ◽  
Fungal Genome ◽  
Fungal Transformation ◽  
Pulsed Field ◽  
Mitotic Instability ◽  
Vigorous Growth ◽  
Exogenous Genes ◽  
Biolistic Process ◽  
Chromosomal Bands

Mitotically unstable Aspergillus nidulans argB+ transformants obtained by the biolistic process were studied in the present work. Hybridization signals from undigested DNA and pulsed-field chromosomal bands of the transformants suggested the introduced plasmid occurred as free concatenated molecules. Fifteen vigorous growth sectors released from the transformants were analysed in order to understand the mechanisms involved in their formation. All sectors showed the integration of exogenous genes into the fungal genome by homologous or heterologous recombinant events.Key words: Aspergillus nidulans, biolistic process, mitotic instability, fungal transformation.

Genetic and molecular analysis of Aspergillus nidulans transformants obtained by the biolistic process

1997 ◽  
Vol 43 (8) ◽  
pp. 718-722
Author(s):  
Maria Helena P. Fungaro ◽  
Regina C. Poli ◽  
Aline A. Pizzirani-Kleiner ◽  
João Lucio Azevedo ◽  
Evelyne Besin ◽  
...  
Keyword(s):  
Aspergillus Nidulans ◽  
Fungal Transformation ◽  
Wild Type Allele ◽  
Wild Type ◽  
Transfer Gene ◽  
Molecular Analyses ◽  
Stable Transformants ◽  
Gene Integration ◽  
Chromosome Iii ◽  
Biolistic Process

Twenty transformants obtained by transforming the argB strain of Aspergillus nidulans by the biolistic process were analysed in detail. Eight lost the Arg+ phenotype very frequently and the other 12 were mitotically stable, even after 15 successive subculturing. To analyse the integration events, the mitotically stable transformants were submited to genetic and molecular analyses; 16.7% resulted from the integration of the transforming DNA in tandem with the chromosomal argB locus, 8.3% showed replacement of the argB mutation by wild type allele, 41.7% showed transforming DNA integrated into nonhomologous chromosomal regions at chromosome III, and 33.3% showed transforming DNA integrated into nonhomologous chromosomal regions at chromosomes others than III. Among the mitotically stable transformants, the frequency of integration into nonhomologous sites was higher by the biolistic process than that reported by the literature for protoplast-mediated transformation.Key words: Aspergillus nidulans, fungal transformation, biolistic gene transfer, gene integration, argB gene.

Genetic analysis of Aspergillus nidulans unstable transformants obtained by the biolistic process

1998 ◽  
Vol 44 (12) ◽  
pp. 1137-1141 ◽  
Author(s):  
Fernando Gomes Barcellos ◽  
Maria Helena Pelegrinelli Fungaro ◽  
Márcia Cristina Furlaneto ◽  
Bernard Lejeune ◽  
Aline A. Pizzirani-Kleiner ◽  
...  
Keyword(s):  
Genetic Analysis ◽  
Aspergillus Nidulans ◽  
Biolistic Process

scholarly journals COMPUTERIZED MEIOTIC MAPPING IN ASPERGILLUS NIDULANS

Genetics ◽  
1972 ◽  
Vol 72 (4) ◽  
pp. 595-605
Author(s):  
Gordon L Dorn
Keyword(s):  
Genetic Analysis ◽  
Aspergillus Nidulans ◽  
Computer System ◽  
Computer Analysis ◽  
Gene Sequences ◽  
Gene Group ◽  
Advantages And Disadvantages ◽  
Meiotic Mapping ◽  
Coefficient Of Coincidence

ABSTRACT A computer system for the storage and processing of microbial meiotic data has been developed. Based on the language Fortran 4, the program retrieves relevant data and determines the order, map distances, and coefficient of coincidence for any three-gene group. Meiotic data from Aspergillus nidulans were used to test the program. A total of 61 three-gene sequences were processed, and the results were found to be compatible with the published values. The advantages and disadvantages of computer analysis for genetic analysis are discussed.

scholarly journals Electrophoretic characterization of Aspergillus nidulans strains with chromosomal duplications

2000 ◽  
Vol 23 (2) ◽  
pp. 293-297 ◽  
Author(s):  
Marisa V. de Queiroz ◽  
Aline Aparecida Pizzirani-Kleiner ◽  
João Lúcio Azevedo
Keyword(s):  
Aspergillus Nidulans ◽  
Gel Electrophoresis ◽  
Chromosomal Rearrangements ◽  
Pulsed Field Gel Electrophoresis ◽  
Electrophoretic Karyotype ◽  
Pulsed Field ◽  
Chromosome Ii ◽  
Chromosome I ◽  
Chromosomal Duplication

Pulsed-field gel electrophoresis was used to characterize strains of Aspergillus nidulans with a chromosomal duplication Dp(I-II). Morphologically deteriorated and improved variants of these strains were also analyzed. The electrophoretic karyotype demonstrated that in two duplicated strains (A and B) the 4.2 Mb band, which corresponds to chromosome II, was absent and a new band was observed. Hybridization studies using the uapA (chromosome I) and wA (chromosome II) genes demonstrated that the new band corresponded to chromosome II plus the duplicated segment of chromosome I. The size of the chromosomal duplication was approximately 1.0 Mb. Analysis of the chromosomal bands of a morphologically improved strain showed that the duplicated segment of chromosome I was completely lost. The morphologically deteriorated variants V9 and V17 had the same karyotype as the duplicated strains. However, the deteriorated variant V5 lost part of chromosome I and had a rearrangement involving chromosome V. This rearrangement may have resulted from the mutagenic treatment used to obtain the genetic markers. Pulsed-field gel electrophoresis was found to be an excellent tool for locating chromosomal rearrangements.

scholarly journals Genetic Analysis of Multiple Vancomycin-ResistantEnterococcus Isolates Obtained Serially from Two Long-Term-Care Patients

1998 ◽  
Vol 36 (7) ◽  
pp. 2105-2108 ◽  
Author(s):  
Dianna J. Schoonmaker ◽  
Lawrence H. Bopp ◽  
Aldona L. Baltch ◽  
Raymond P. Smith ◽  
Mary Ellen Rafferty ◽  
...  
Keyword(s):  
High Risk ◽  
Genetic Analysis ◽  
Gel Electrophoresis ◽  
Long Term Care ◽  
Pulsed Field Gel Electrophoresis ◽  
Risk Of Infection ◽  
Term Care ◽  
Pulsed Field ◽  
Vancomycin Resistant

Fifty-eight vancomycin-resistant enterococcal isolates were obtained from two patients over 9 weeks. Numerous pulsed-field gel electrophoresis fingerprinting types were isolated from each patient. By PCR, all isolates were vanA +. However, many isolates from patient B were found to lack vanA by hybridization. Our results demonstrate the importance of examining multiple isolates, especially from patients who are at high risk of infection.

scholarly journals Genetic analysis of the phosphatases in Aspergillus nidulans

1965 ◽  
Vol 6 (1) ◽  
pp. 13-26 ◽  
Author(s):  
G. Dorn
Keyword(s):  
Alkaline Phosphatase ◽  
Acid Phosphatase ◽  
Genetic Analysis ◽  
Aspergillus Nidulans ◽  
Alkaline Ph ◽  
Wild Type ◽  
Linkage Groups ◽  
Partial Restoration ◽  
Suppressor Mutations ◽  
Alkaline And Acid Phosphatase

Summary1. A histochemical method has been applied to the detection of alkaline and acid phosphatase mutants in single colonies of Aspergillus nidulans.2. With the above method it has been possible to isolate mutants in which the alkaline and acid phosphatase activities are affected either separately or simultaneously.3. Crude extracts of wild-type A. nidulans contain four electrophoretically distinct phosphatase components, two with activity at alkaline pH and two with activity at acid pH. Genes affecting three of the four components have been identified.4. Two suppressor mutants of an alkaline phosphataseless mutant (palB7) have been isolated. In a strain carrying palB7 and one of these suppressors, the restoration of an alkaline phosphatase component is accompanied by loss of the faster acid phosphatase component. In a similar strain carrying the other suppressor, the partial restoration of the alkaline phosphatase component goes with an electrophoretic alteration of the slower acid phosphatase component.5. Genetic analysis of twenty-seven mutants has resulted in the identification of fifteen loci affecting the phosphatases. All these loci have been assigned to linkage groups, and twelve of them were also mapped meiotically in relation to other loci.6. One possible model (based on heteropolymeric proteins) has been proposed to account for the electrophoretic and genetic data on the various phosphatase and suppressor mutations.

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