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2.
Appl Environ Microbiol ; 67(8): 3385-90, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11472908

ABSTRACT

The edible fungus Pleurotus ostreatus (oyster mushroom) is an industrially produced heterothallic homobasidiomycete whose mating is controlled by a bifactorial tetrapolar genetic system. Two mating loci (matA and matB) control different steps of hyphal fusion, nuclear migration, and nuclear sorting during the onset and progress of the dikaryotic growth. Previous studies have shown that the segregation of the alleles present at the matB locus differs from that expected for a single locus because (i) new nonparental B alleles appeared in the progeny and (ii) there was a distortion in the segregation of the genomic regions close to this mating locus. In this study, we pursued these observations by using a genetic approach based on the identification of molecular markers linked to the matB locus that allowed us to dissect it into two genetically linked subunits (matBalpha and matBbeta) and to correlate the presence of specific matBalpha and matA alleles with differences in monokaryotic growth rate. The availability of these molecular markers and the mating type dependence of growth rate in monokaryons can be helpful for marker-assisted selection of fast-growing monokaryons to be used in the construction of dikaryons able to colonize the substrate faster than the competitors responsible for reductions in the industrial yield of this fungus.


Subject(s)
Gene Expression Regulation, Fungal , Pleurotus/genetics , Pleurotus/physiology , Alleles , Bacterial Proteins/genetics , Chromosome Mapping , Crosses, Genetic , Genetic Markers , Polymorphism, Restriction Fragment Length , Random Amplified Polymorphic DNA Technique
3.
FEMS Microbiol Lett ; 198(1): 45-8, 2001 Apr 20.
Article in English | MEDLINE | ID: mdl-11325552

ABSTRACT

Agaricus bisporus is an edible basidiomycete cultivated industrially for food production. Different spawn and mushroom producers use genetically related A. bisporus strains frequently marketed as different products. In this paper we show that the use of suitable molecular markers reveals the high level of genetic homology of commercial strains of A. bisporus, and allows, at the same time, to distinguish between them. In the course of this work, a molecular marker potentially linked to the agronomic character 'mushroom weight' has been identified by bulked segregant analysis.


Subject(s)
Agaricus/classification , Agaricus/genetics , Genetic Variation , DNA Fingerprinting , DNA Primers , DNA Probes , Genetic Markers , Mycological Typing Techniques , Oligonucleotides , Polymerase Chain Reaction
4.
Int Microbiol ; 4(1): 13-9, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11770815

ABSTRACT

Bacteriocins are ribosomally synthesized antimicrobial peptides produced by microorganisms belonging to different eubacterial taxonomic branches. Most of them are small cationic membrane-active compounds that form pores in the target cells, disrupting membrane potentials and causing cell death. The production of small cationic peptides with antibacterial activity is a defense strategy found not only in bacteria, but also in plants and animals. Bacteriocins are classified according to different criteria by different authors; in this review, we will summarize the principal bacteriocin classifications, highlight their main physical and chemical characteristics, and describe the mechanism of some selected bacteriocins that act at the membrane level.


Subject(s)
Bacteriocins/classification , Bacteriocins/pharmacology , Gram-Positive Bacteria/physiology , Bacteriocins/biosynthesis , Cell Membrane/drug effects , Models, Biological
5.
Int Microbiol ; 3(3): 147-52, 2000 Sep.
Article in English | MEDLINE | ID: mdl-11032306

ABSTRACT

The industrial production of edible basidiomycetes is increasing every year as a response to the increasing public demand of them because of their nutritional properties. About a dozen of fungal species can be currently produced for food with sound industrial and economic bases. Notwithstanding, this production is threatened by biotic and abiotic factors that make it necessary to improve the fungal strains currently used in industry. Breeding of edible basidiomycetes, however, has been mainly empirical and slow since the genetic tools useful in the selection of the new genetic material to be introduced in the commercial strains have not been developed for these fungi as it was for other organisms. In this review we will discuss the main genetic factors that should be considered to develop breeding approaches and tools for higher basidiomycetes. These factors are (i) the genetic system controlling fungal mating; (ii) the genomic structure and organisation of these fungi; and (iii) the identification of genes involved in the control of quantitative traits. We will discuss the weight of these factors using the oyster mushroom Pleurotus ostreatus as a model organism for most of the edible fungi cultivated industrially.


Subject(s)
Basidiomycota/growth & development , Food Industry/methods , Industrial Microbiology/methods , Mycology/methods , Alleles , Basidiomycota/genetics , Basidiomycota/physiology , Breeding , Chromosomes, Fungal/genetics , Genes, Fungal , Genetic Linkage , Genome, Fungal , Pleurotus/genetics , Pleurotus/physiology , Polymorphism, Restriction Fragment Length , Quantitative Trait, Heritable , Random Amplified Polymorphic DNA Technique , Reproduction
6.
Appl Environ Microbiol ; 66(12): 5290-300, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11097904

ABSTRACT

We have constructed a genetic linkage map of the edible basidiomycete Pleurotus ostreatus (var. Florida). The map is based on the segregation of 178 random amplified polymorphic DNA and 23 restriction fragment length polymorphism markers; four hydrophobin, two laccase, and two manganese peroxidase genes; both mating type loci; one isozyme locus (est1); the rRNA gene sequence; and a repetitive DNA sequence in a population of 80 sibling monokaryons. The map identifies 11 linkage groups corresponding to the chromosomes of P. ostreatus, and it has a total length of 1,000.7 centimorgans (cM) with an average of 35.1 kbp/cM. The map shows a high correlation (0.76) between physical and genetic chromosome sizes. The number of crossovers observed per chromosome per individual cell is 0.89. This map covers nearly the whole genome of P. ostreatus.


Subject(s)
Pleurotus/genetics , Chromosome Mapping , Chromosomes, Fungal/genetics , DNA, Fungal/genetics , Electrophoresis, Gel, Pulsed-Field , Genes, Fungal , Genes, Mating Type, Fungal , Genetic Linkage , Genetic Markers , Isoenzymes/genetics , Phenotype , Pleurotus/enzymology , Polymorphism, Restriction Fragment Length
7.
J Appl Microbiol ; 89(2): 361-9, 2000 Aug.
Article in English | MEDLINE | ID: mdl-10971770

ABSTRACT

Cerein 7 is a peptidic antibiotic produced by Bacillus cereus Bc7 (CECT 5148) at the end of exponential growth but before sporulation onset. Cerein 7 has a broad spectrum of antibacterial activity against Gram-positive bacteria, but it is inactive against Gram-negative bacteria. The sequence of its amino-terminal end and its characteristics of hydrophobicity and molecular mass make cerein 7 unique among the bacteriocins produced by the soil bacterium B. cereus. In this paper a further characterization of cerein 7 is presented, it is shown that it can be classified as a Klaenhammer's class II bacteriocin and that its mode of action corresponds to that of a membrane-active compound.


Subject(s)
Bacillus cereus/growth & development , Bacteriocins/metabolism , Bacteriocins/pharmacology , Gram-Positive Bacteria/drug effects , Bacillus cereus/metabolism , Bacteriocins/classification , Bacteriocins/isolation & purification , Bacteriolysis , Colony Count, Microbial , Dose-Response Relationship, Drug , Gram-Positive Bacteria/growth & development , Microbial Sensitivity Tests
8.
Syst Appl Microbiol ; 23(1): 15-24, 2000 Apr.
Article in English | MEDLINE | ID: mdl-10879974

ABSTRACT

The cephamycin producer strain 'Nocardia lactamdurans' contains four ribosomal RNA (rrn) operons. One of them (rrnD) was cloned from a DNA library in the bifunctional cosmid pJAR4. A 2229 bp region of rrnD has been sequenced. The 'N. lactamdurans' rrnD operon maintains the canonical order 5'-16S-23S-5S-3'. Four of the consensus Gürtler-Stanisch sequences were found in the 16S rRNA gene and a fifth one in the sequenced 5' region of the 23S rRNA gene. The anti Shine-Dalgarno sequence of 'N. lactamdurans' (located in the 3'-end of the 16S rRNA gene) was found to be 5'-CCUCCUUUCU-3' and is identical to that of Corynebacterium lactofermentum and Mycobacterium tuberculosis. A phylogenetic analysis of 'N. lactamdurans' by the neighbor-joining method using the entire 16S rRNA nucleotide sequence revealed that this actinomycete is closely related to Amlycolatopsis orientalis subsp orientalis, Amycolatopsis coloradensis, Amycolatopsis alba, Amycolatopsis sulphurea and other Amycolatopsis sp. but only distantly related to species of the genus Nocardia. The cephamycin producer 'N. lactamdurans' NRRL 3802 should be, therefore, classified as Amycolatopsis lactamdurans. The deduced secondary structure of the 16S rRNA is very similar to that of A. colorandensis and A. alba but different from those of species of the Nocardia genus supporting the incorporation of 'N. lactamdurans' into the genus Amycolatopsis.


Subject(s)
Actinomycetales/classification , Cephamycins/biosynthesis , Nocardia/classification , rRNA Operon , Actinomycetales/genetics , Actinomycetales/metabolism , Base Sequence , Cloning, Molecular , DNA, Bacterial/analysis , DNA, Bacterial/genetics , DNA, Ribosomal/analysis , DNA, Ribosomal/genetics , DNA, Ribosomal Spacer/genetics , Genes, rRNA , Molecular Sequence Data , Nocardia/genetics , Nocardia/metabolism , Nucleic Acid Conformation , Phylogeny , Plasmids , RNA, Bacterial/chemistry , RNA, Bacterial/genetics , RNA, Ribosomal, 16S/chemistry , RNA, Ribosomal, 16S/genetics , RNA, Ribosomal, 23S/genetics , Restriction Mapping , Sequence Analysis, DNA , Terminator Regions, Genetic
9.
FEMS Microbiol Lett ; 178(2): 337-41, 1999 Sep 15.
Article in English | MEDLINE | ID: mdl-10499284

ABSTRACT

A bacteriocin-producing strain of Bacillus cereus was identified and isolated from a soil sample. The bacteriocin could be purified by a two-step procedure: ammonium sulfate precipitation of culture supernatants followed by a butanol extraction step, the antibiotic was recovered from the organic phase. The peptidic nature of the bacteriocin was proven by its sensitivity to proteolytic enzymes; its molecular mass, determined by mass spectrometry, was 3940 Da; and its amino-terminal sequence (GWGDVL) is unique in the databases. The compound was active against most Gram-positive but not Gram-negative bacteria. This is to our knowledge the first bacteriocin with these characteristics reported to be produced by B. cereus.


Subject(s)
Bacillus cereus/metabolism , Bacteriocins/isolation & purification , Bacteriocins/pharmacology , Gram-Negative Bacteria/drug effects , Gram-Positive Bacteria/drug effects , Bacillus cereus/growth & development , Bacteriocins/biosynthesis , Mass Spectrometry , Microbial Sensitivity Tests
10.
Appl Environ Microbiol ; 65(8): 3413-7, 1999 Aug.
Article in English | MEDLINE | ID: mdl-10427028

ABSTRACT

The white rot fungus Pleurotus ostreatus is an edible basidiomycete with increasing agricultural and biotechnological importance. Genetic manipulation and breeding of this organism are restricted because of the lack of knowledge about its genomic structure. In this study, we analyzed the genomic constitution of P. ostreatus by using pulsed-field gel electrophoresis optimized for the separation of its chromosomes. We have determined that it contains 11 pairs of chromosomes with sizes ranging from 1.4 to 4.7 Mbp. In addition to chromosome separation, the use of single-copy DNA probes allowed us to resolve the ambiguities caused by chromosome comigration. When the two nuclei present in the dikaryon were separated by protoplasting, analysis of their karyotypes revealed length polymorphisms affecting various chromosomes. This is, to our knowledge, the clearest chromosome separation available for this species.


Subject(s)
Pleurotus/genetics , Base Sequence , Chromosomes, Fungal/genetics , DNA Probes/genetics , Electrophoresis, Gel, Pulsed-Field , Karyotyping , Molecular Sequence Data
11.
Curr Genet ; 34(6): 486-93, 1999 Jan.
Article in English | MEDLINE | ID: mdl-9933361

ABSTRACT

Pleurotus ostreatus is a hetertothallic homobasidiomycete whose mating is controlled by a bifactorial tetrapolar genetic system. Although this mechanism is well accepted, there is a lack of knowledge about its molecular basis, as the incompatibility loci have not been cloned and sequenced. As a first step towards the elucidation of the molecular structure of the A-type incompatibility locus, molecular markers have been isolated which correspond to genomic sequences present in different strains of P. ostreatus but not in other higher basidiomycetae. These markers reveal single-copy genetic regions in which some degree of genetic variability can be detected.


Subject(s)
Genes, Fungal , Pleurotus/genetics , Alleles , Chromosome Mapping , Genetic Linkage , Genetic Markers , Genetic Variation , Meiosis/genetics , Pleurotus/growth & development , Polymorphism, Restriction Fragment Length , Random Amplified Polymorphic DNA Technique
12.
Appl Environ Microbiol ; 64(10): 4028-34, 1998 Oct.
Article in English | MEDLINE | ID: mdl-9758836

ABSTRACT

Hydrophobins are small (length, about 100 +/- 25 amino acids), cysteine-rich, hydrophobic proteins that are present in large amounts in fungal cell walls, where they form part of the outermost layer (rodlet layer); sometimes, they can also be secreted into the medium. Different hydrophobins are associated with different developmental stages of a fungus, and their biological functions include protection of the hyphae against desiccation and attack by either bacterial or fungal parasites, hyphal adherence, and the lowering of surface tension of the culture medium to permit aerial growth of the hyphae. We identified and isolated a hydrophobin (fruit body hydrophobin 1 [Fbh1]) present in fruit bodies but absent in both monokaryotic and dikaryotic mycelia of the edible mushroom Pleurotus ostreatus. In order to study the temporal and spatial expression of the fbh1 gene, we determined the N-terminal amino acid sequence of Fbh1. We also synthesized and cloned the double-stranded cDNA corresponding to the full-length mRNA of Fbh1 to use it as a probe in both Northern blot and in situ hybridization experiments. Fbh1 mRNA is detectable in specific parts of the fruit body, and it is absent in other developmental stages.


Subject(s)
Fungal Proteins/biosynthesis , Pleurotus/physiology , Agaricales , Amino Acid Sequence , Base Sequence , Blotting, Northern , Cell Membrane/ultrastructure , Cloning, Molecular , DNA, Complementary , Escherichia coli , Fungal Proteins/chemistry , Fungal Proteins/genetics , Genes, Fungal , In Situ Hybridization , Molecular Sequence Data , Pleurotus/genetics , RNA, Messenger/analysis , Recombinant Proteins/analysis , Recombinant Proteins/biosynthesis , Recombinant Proteins/chemistry , Transcription, Genetic
13.
Curr Microbiol ; 36(5): 302-8, 1998 May.
Article in English | MEDLINE | ID: mdl-9541568

ABSTRACT

Total DNA of virulent and avirulent strains of Rhodococcus fascians was resolved by pulsed-field gel electrophoresis (PFGE) into a discrete number of fragments by digestion with the endonucleases AseI and DraI. Restriction endonucleases PacI, PmeI, and SwaI yielded no fragments upon digestion of R. fascians genome, and all the other tested endonucleases recognizing 6 bp released too many fragments. The genome size was 5.6 megabases for the type strain R. fascians DSM 20669, and 5.8 megabases for the virulent R. fascians D188 strain. However the genome size of R. fascians CECT 3001 (NRRL B15096) was 8.0 megabases. No linear chromosome in the megabase range was observed under pulse conditions in which Saccharomyces cerevisiae and Schizosaccharomyces pombe chromosomes were perfectly resolved, suggesting that the R. fascians chromosome is circular. A new linear plasmid pIRN640 of 640 kb was found in the avirulent R. fascians CECT 3001 that did not hybridize with a probe internal to the fas region of pFiD188 known to be involved in plant pathogenicity in the virulent strain R. fascians D188. Virulence was correlated in all strains tested with the presence of the fas region. The AseI and DraI bands corresponding to the extrachromosomal elements were identified providing the basis for a physical map of this organism.


Subject(s)
Genome, Bacterial , Replicon , Rhodococcus/genetics , DNA, Circular , Deoxyribonucleases, Type II Site-Specific , Electrophoresis, Gel, Pulsed-Field , Genetic Code , Markov Chains , Nucleic Acid Conformation , Restriction Mapping , Rhodococcus/classification , Rhodococcus/pathogenicity , Species Specificity
14.
Appl Environ Microbiol ; 64(4): 1276-82, 1998 Apr.
Article in English | MEDLINE | ID: mdl-9546162

ABSTRACT

A 6.0-kb SalI DNA fragment containing an entire rRNA operon (rrnB) was cloned from a cosmid gene bank of the phytopathogenic strain Rhodococcus fascians D188. The nucleotide sequence of the 6-kb fragment was determined and had the organization 16S rRNA-spacer-23S rRNA-spacer-5S rRNA without tRNA-encoding genes in the spacer regions. The 5' and 3' ends of the mature 16S, 23S, and 5S rRNAs were determined by alignment with the rrn operons of Bacillus subtilis and other gram-positive bacteria. Four copies of the rrn operons were identified by hybridization with an rrnB probe in R. fascians type strain ATCC 12974 and in the virulent strain R. fascians D188. However, another isolate, CECT 3001 (= NRRL B15096), also classified as R. fascians, produced five rrn-hybridizing bands. An integrative vector containing a 2.5-kb DNA fragment internal to rrnB was constructed for targeted integration of exogenous genes at the rrn loci. Transformants carrying the exogenous chloramphenicol resistance gene (cmr) integrated in different rrn operons were obtained. These transformants had normal growth rates in complex medium and minimal medium and were fully stable for the integrated marker.


Subject(s)
Genes, Bacterial , Plants/microbiology , Rhodococcus/genetics , Rhodococcus/pathogenicity , Base Sequence , Cloning, Molecular , DNA, Bacterial/genetics , DNA, Ribosomal/genetics , Gene Targeting , Genetic Vectors , Molecular Sequence Data , Operon , RNA, Bacterial/genetics , RNA, Ribosomal, 16S/genetics , RNA, Ribosomal, 23S/genetics , RNA, Ribosomal, 5S/genetics , Restriction Mapping , Sequence Homology, Nucleic Acid , Virulence/genetics
15.
Gene ; 170(1): 91-4, 1996 Apr 17.
Article in English | MEDLINE | ID: mdl-8621097

ABSTRACT

A repetitive DNA element of the Gram+ Brevibacterium lactofermentum (Bl), cloned by a modification of the subtractive hybridization method, contained a 1.4-kb IS-like element, IS13869, which included an open reading frame (ORF) inside a perfect 26-bp terminal inverted repeat (TIR). An 8-bp direct repeat (DR) was found outside each TIR. The ORF encoded a deduced protein of 436 amino acids (49 380 Da) with extensive similarity to other known transposases of insertion elements of Mycobacterium smegmatis (IS1096). Pseudomonas sp. (tpnA) and Corynebacterium glutamicum (IS31831). Distinct patterns were observed in different strains of Bl by hybridization with a probe internal to IS13869: four copies of IS13869 occurred in the wild type (wt) and R31 strains, but only three of them were observed in a recA derivative of the wt. Analysis by pulsed-field gel electrophoresis suggested that at least one copy of IS13869 had changed its position inside the chromosome during the lineage of a Bl derivative.


Subject(s)
Bacterial Proteins/genetics , Brevibacterium/genetics , DNA Nucleotidyltransferases/genetics , DNA Transposable Elements/genetics , DNA, Bacterial/genetics , Base Sequence , Cloning, Molecular , Electrophoresis, Gel, Pulsed-Field , Molecular Sequence Data , Molecular Weight , Repetitive Sequences, Nucleic Acid , Sequence Alignment , Sequence Homology, Nucleic Acid , Species Specificity , Subtraction Technique , Transposases
16.
J Bacteriol ; 177(4): 992-7, 1995 Feb.
Article in English | MEDLINE | ID: mdl-7860611

ABSTRACT

The penicillin tolerance of amino acid-deprived relA+ Escherichia coli is attributed to the stringent response; i.e., relaxation of the stringent response suppresses penicillin tolerance. The beta-lactam-induced lysis of amino acid-deprived bacteria resulting from relaxation of the stringent response was inhibited by cerulenin, or by glycerol deprivation in the case of a gpsA mutant (defective in the biosynthetic sn-glycerol 3-phosphate dehydrogenase). Therefore, beta-lactam-induced lysis of amino acid-deprived cells was dependent on phospholipid synthesis. The lysis process during amino acid deprivation can be experimentally dissociated into two stages designated the priming stage (during which the interaction between the beta-lactam and the penicillin-binding proteins occurs) and the beta-lactam-independent lysis induction stage. Both stages were shown to require phospholipid synthesis. It has been known for some time that the inhibition of phospholipid synthesis is among the plethora of physiological changes resulting from the stringent response. These results indicate that the inhibition of peptidoglycan synthesis and the penicillin tolerance associated with the stringent response are both secondary consequences of the inhibition of phospholipid synthesis.


Subject(s)
Ampicillin/pharmacology , Bacteriolysis/physiology , Escherichia coli/drug effects , Isoleucine/deficiency , Phospholipids/biosynthesis , Bacteriolysis/drug effects , Cerulenin/pharmacology , Escherichia coli/metabolism , Glycerol/metabolism , Ligases , Models, Biological , Penicillin Resistance/physiology
17.
J Bacteriol ; 176(23): 7362-71, 1994 Dec.
Article in English | MEDLINE | ID: mdl-7961509

ABSTRACT

Two genes, hom (encoding homoserine dehydrogenase) and thrB (encoding homoserine kinase), of the threonine biosynthetic pathway are clustered in the chromosome of Brevibacterium lactofermentum in the order 5' hom-thrB 3', separated by only 10 bp. The Brevibacterium thrB gene is expressed in Escherichia coli, in Brevibacterium lactofermentum, and in Corynebacterium glutamicum and complements auxotrophs of all three organisms deficient in homoserine kinase, whereas the Brevibacterium hom gene did not complement two different E. coli auxotrophs lacking homoserine dehydrogenase. However, complementation was obtained when the homoserine dehydrogenase was expressed as a fusion protein in E. coli. Northern (RNA) analysis showed that the hom-thrB cluster is transcribed, giving two different transcripts of 2.5 and 1.1 kb. The 2.5-kb transcript corresponds to the entire cluster hom-thrB (i.e., they form a bicistronic operon), and the short transcript (1.1 kb) originates from the thrB gene. The promoter in front of hom and the hom-internal promoter in front of thrB were subcloned in promoter-probe vectors of E. coli and corynebacteria. The thrB promoter is efficiently recognized both in E. coli and corynebacteria, whereas the hom promoter is functional in corynebacteria but not in E. coli. The transcription start points of both promoters have been identified by primer extension and S1 mapping analysis. The thrB promoter was located in an 87-bp fragment that overlaps with the end of the hom gene. A functional transcriptional terminator located downstream from the cluster was subcloned in terminator-probe vectors.


Subject(s)
Brevibacterium/genetics , Homoserine Dehydrogenase/genetics , Multigene Family/genetics , Phosphotransferases (Alcohol Group Acceptor)/genetics , Regulatory Sequences, Nucleic Acid/genetics , Amino Acid Sequence , Base Sequence , Cloning, Molecular , Corynebacterium/genetics , Escherichia coli/genetics , Gene Expression Regulation, Bacterial , Genetic Complementation Test , Molecular Sequence Data , Promoter Regions, Genetic/genetics , RNA, Messenger/genetics , Terminator Regions, Genetic/genetics , Transcription, Genetic
18.
J Bacteriol ; 175(22): 7356-62, 1993 Nov.
Article in English | MEDLINE | ID: mdl-8226683

ABSTRACT

The Brevibacterium lactofermentum argS gene, which encodes an arginyl-tRNA synthetase, was identified in the upstream region of the lysA gene. The cloned gene was sequenced; it encodes a 550-amino-acid protein with an M(r) of 59,797. The deduced amino acid sequence showed 28% identical and 49% similar residues when compared with the sequence of the Escherichia coli arginyl-tRNA synthetase. The B. lactofermentum enzyme showed the highly conserved motifs of class I aminoacyl-tRNA synthetases. Expression of the argS gene in B. lactofermentum and E. coli resulted in an increase in aminoacyl-tRNA synthetase activity, correlated with the presence in sodium dodecyl sulfate-polyacrylamide gels of a clear protein band that corresponds to this enzyme. One single transcript of about 3,000 nucleotides and corresponding to the B. lactofermentum argS-lysA operon was identified. The transcription of these genes is repressed by lysine and induced by arginine, showing an interesting pattern of biosynthetic interlock between the pathways of both amino acids in corynebacteria.


Subject(s)
Arginine-tRNA Ligase/genetics , Arginine/pharmacology , Bacterial Proteins , Brevibacterium/enzymology , Brevibacterium/genetics , Carboxy-Lyases/genetics , Gene Expression Regulation, Bacterial/drug effects , Genes, Bacterial , Multigene Family , Amino Acid Sequence , Amino Acyl-tRNA Synthetases/genetics , Arginine-tRNA Ligase/biosynthesis , Bacteria/enzymology , Cloning, Molecular , Escherichia coli/genetics , Escherichia coli/growth & development , Fungi/enzymology , Gene Expression Regulation, Enzymologic/drug effects , Molecular Sequence Data , Molecular Weight , Plasmids , Restriction Mapping , Sequence Homology, Amino Acid
19.
J Bacteriol ; 175(9): 2743-9, 1993 May.
Article in English | MEDLINE | ID: mdl-8478336

ABSTRACT

The dapA and dapB genes, encoding, respectively, dihydrodipicolinate synthase and dihydrodipicolinate reductase, the two first enzymes of the lysine branch of the aspartic amino acid family, were cloned from the DNA of the amino acid-producing bacterium Brevibacterium lactofermentum. The two genes were clustered in a 3.5-kb Sau3AI-BamHI fragment but were separated by an open reading frame of 750 nucleotides. The protein encoded by this open reading frame had little similarity to any protein in the data banks, and its function remains unknown. The three genes were translated in Escherichia coli, giving the corresponding polypeptides.


Subject(s)
Brevibacterium/genetics , Genes, Bacterial/genetics , Hydro-Lyases/genetics , Oxidoreductases Acting on CH-CH Group Donors , Oxidoreductases/genetics , Amino Acid Sequence , Base Sequence , Brevibacterium/enzymology , Chromosome Mapping , Cloning, Molecular , Dihydrodipicolinate Reductase , Escherichia coli/genetics , Genetic Complementation Test , Lysine/biosynthesis , Molecular Sequence Data , Multigene Family/genetics , Open Reading Frames/genetics , Restriction Mapping , Sequence Deletion , Sequence Homology, Amino Acid
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