Isolation and characterization of nocardia-like variants of Mycobacterium smegmatis

1976 ◽  
Vol 22 (10) ◽  
pp. 1480-1491 ◽  
Author(s):  
R. J. Hawley ◽  
T. Imaeda ◽  
Nora Mann
Keyword(s):  
Fatty Acids ◽  
Mitomycin C ◽  
Ultraviolet Light ◽  
Mycobacterium Smegmatis ◽  
Deoxyribonucleic Acid ◽  
New Class ◽  
Parental Type ◽  
Isolation And Characterization ◽  
Hydroxylated Fatty Acids

Orange-red-pigmented (OR) colonies were isolated from cream-yellow-pigmented Mycobacterium smegmatis after exposure to either mycobacteriophage MC4 or ultraviolet light; these variant strains were designated OR4 and ORuv, respectively. Early subculture of OR-colonies did not show any segregation of parental-type cells. However, colonies resembling the parental strains, possibly representing a back mutant (REV-OR4), were occasionally found during subculture of established OR-colonies or upon treatment with N-nitroso-N′-nitro-N-methylguanidine. The OR-variants were characterized by their lytic response to nocardiophage, but not to mycobacteriophages, presence of α-branched, β-hydroxylated fatty acids of the Nocardia-type, and a guanine plus cytosine value of deoxyribonucleic acid (DNA) between 62 and 64 mol %. They were more resistant to the lethal action of both ultraviolet light and mitomycin C treatment than the parental and back mutant strains.Although the OR-variants in this study possess characteristics common to the genus Nocardia or some of the 'rhodochrous' mycobacteria, evidence is presented that they form a new class of mycobacterial variants.

Characterization of Aeromonas genomic species by using quinone, polyamine, and fatty acid patterns

1994 ◽  
Vol 40 (10) ◽  
pp. 844-850 ◽  
Author(s):  
Peter Kämpfer ◽  
Klaus Blasczyk ◽  
Georg Auling
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Octadecenoic Acid ◽  
Hexadecenoic Acid ◽  
Genomic Species ◽  
Great Homogeneity ◽  
Hydroxylated Fatty Acids ◽  
Fatty Acid Patterns ◽  
Chemotaxonomic Study

A chemotaxonomic study was carried out on representative strains of 13 Aeromonas genomic species. Quinone, polyamine, and fatty acid patterns were found to be very useful for an improved characterization of the genus and an improved differentiation from members of the families Enterobacteriaceae and Vibrionaceae. The Q-8-benzoquinone was the predominant ubiquinone, and putrescine and diaminopropane were the major poly amines of the genus. The fatty acid patterns of 181 strains, all characterized by DNA–DNA hybridization, showed a great homogeneity within the genus, with major amounts of hexadecanoic acid (16:0), hexadecenoic acid (16:1), and octadecenoic acid (18:1), and minor amounts of the hydroxylated fatty acids (3-OH 13:0, 2-OH 14:0, 3-OH 14:0) in addition to some iso and anteiso branched fatty acids (i-13:0, i-17:1, i-17:0, and a-17:0). Although some differences in fatty acid profiles between the genomic species could be observed, a clearcut differentiation of all species was not possible.Key words: Aeromonas, polyamines, quinones, fatty acids, differentiation.

scholarly journals Isolation and Characterization of Thermosensitive Escherichia coli Mutants Defective in Deoxyribonucleic Acid Replication

1973 ◽  
Vol 113 (3) ◽  
pp. 1381-1388 ◽  
Author(s):  
James A. Wechsler ◽  
Volker Nüsslein ◽  
Bernd Otto ◽  
Albrecht Klein ◽  
Friedrich Bonhoeffer ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Deoxyribonucleic Acid ◽  
Isolation And Characterization

scholarly journals Isolation and characterization of the dopa decarboxylase gene of Drosophila melanogaster

1981 ◽  
Vol 1 (6) ◽  
pp. 475-485
Author(s):  
J Hirsh ◽  
N Davidson
Keyword(s):  
Drosophila Melanogaster ◽  
Ribonucleic Acid ◽  
Deoxyribonucleic Acid ◽  
Isolation Procedure ◽  
Chromosome Band ◽  
Dopa Decarboxylase ◽  
Developmental Profile ◽  
Isolation And Characterization

We have isolated chromosomal deoxyribonucleic acid clones containing the Drosophila dopa decarboxylase gene. We describe an isolation procedure which can be applied to other nonabundantly expressed Drosophila genes. The dopa decarboxylase gene lies within or very near polytene chromosome band 37C1-2. The gene is interrupted by at least one intron, and the primary mode of regulation is pretranslational. At least two additional sequences hybridized by in vivo ribonucleic acid-derived probes are found within a 35-kilobase region surrounding the gene. The developmental profile of ribonucleic acid transcribed from one of these regions differs from that of the dopa decarboxylase transcript.

Purification and characterization of C28–55 fatty acids from Mycobacterium smegmatis

1985 ◽  
Vol 31 (3) ◽  
pp. 214-219 ◽  
Author(s):  
Neeraja Sathyamoorthy ◽  
Nilofer Qureshi ◽  
Kuni Takayama
Keyword(s):  
Fatty Acids ◽  
Mycobacterium Smegmatis ◽  
High Performance ◽  
Mycolic Acid ◽  
Argentation Thin Layer Chromatography ◽  
Mycolic Acids ◽  
Electron Impact Mass ◽  
Layer Chromatography ◽  
Impact Mass

The nonmycolic C16 to C55 fatty acids obtained from Mycobacterium smegmatis ATCC 356 by saponification were enriched with respect to the C28 to C55 acids by successive chromatography on silicic acid and Sephadex LH-20 columns. These partially purified fatty acids were then derivatized to the p-bromophenacyl ester and further fractionated by argentation thin-layer chromatography and reverse-phase high-performance liquid chromatography into their individual components.The esters were characterized by electron impact mass spectrometry. Two structural series of C28:1 to C42:1 and C45:2 to C55:2 fatty acids were identified as possible precursors of the monoenyl and dienyl mycolic acids, respectively. These acids were structurally related to the α-alkylhydroxyl group of the corresponding mycolic acid. The results suggest that these C28 to C55 fatty acids (meromycolic acids) of M. smegmatis might be precursors of mycolic acids.

scholarly journals Isolation and characterization of mutants that produce the allantoin-degrading enzymes constitutively in Saccharomyces cerevisiae.

1982 ◽  
Vol 2 (9) ◽  
pp. 1088-1095 ◽  
Author(s):  
G Chisholm ◽  
T G Cooper
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Enzyme Synthesis ◽  
Common Element ◽  
Transport Systems ◽  
New Class ◽  
Degrading Enzymes ◽  
Isolation And Characterization ◽  
Nitrogen Repression ◽  
Internal Induction

Degradation of allantoin, allantoate, or urea by Saccharomyces cerevisiae requires the participation of four enzymes and four transport systems. Production of the four enzymes and one of the active transport systems is inducible; allophanate, the last intermediate of the pathway, functions as the inducer. The involvement of allophanate in the expression of five distinct genes suggested that they might be regulated by a common element. This suggestion is now supported by the isolation of a new class of mutants (dal80). Strains possessing lesions in the DAL80 locus produce the five inducible activities at high, constitutive levels. Comparable constitutive levels of activity were also observed in doubly mutant strains (durl dal80) which are unable to synthesize allophanate. This, with the observation that arginase activity remained at its uninduced, basal level in strains mutated at the DAL80 locus, eliminates internal induction as the basis for constitutive enzyme synthesis. Mutations in dal80 are recessive to wild-type alleles. The DAL80 locus has been located and is not linked to any of the structural genes of the allantoin pathway. Synthesis of the five enzymes produced constitutively in dal80-1-containing mutants remains normally sensitive to nitrogen repression even though the dal80-1 mutation is present. From these observations we conclude that production of the allantoin-degrading enzymes is regulated by the DAL80 gene product and that induction and repression of enzyme synthesis can be cleanly separated mutationally.

Isolation and characterization of mitomycin-C-sensitive mouse lymphoma cell mutants

1983 ◽  
Vol 108 (1-3) ◽  
pp. 405-416 ◽  
Author(s):  
Hiroko Hama-Inaba ◽  
Naoko Hieda-Shiomi ◽  
Tadahiro Shiomi ◽  
Koki Sato
Keyword(s):  
Mitomycin C ◽  
Lymphoma Cell ◽  
Isolation And Characterization ◽  
Mouse Lymphoma
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