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PubMed1996

Chromosomal organization of TOX2, a complex locus controlling host-selective toxin biosynthesis in Cochliobolus carbonum.

Race 1 isolates of the filamentous fungus Cochliobolus carbonum are exceptionally virulent on certain genotypes of maize due to production of a cyclic tetrapeptide, HC-toxin. In crosses between toxin-producing (Tox2+) and toxin-nonproducing (Tox2-) isolates, toxin production segregates in a simple 1:1 pattern, suggesting the involvement of a single genetic locus, which has been named TOX2. Earlier work had shown that in isolate SB111, TOX2 consists in part of two copies of a gene, HTS1, that encodes a 570-kD cyclic peptide synthetase and is lacking in Tox2- isolates. The genomic structure of TOX2 and the relationship between the two copies of HTS1 have now been clarified by using pulsedfield gel electrophoresis and physical mapping. In isolate SB111, both copies of HTS1 are on the largest chromosome (3.5 Mb), which is not present in the related Tox2- strain SB114. Two other genes known or thought to be important for HC-toxin biosynthesis, TOXA and TOXC, are also on the same chromosome in multiple copies. Other independent Tox2+ isolates also have two linked copies of HTS1, but in some isolates the size of the chromosome containing HTS1 is 2.2 Mb. Evidence obtained with Tox2+ -unique and with random probes is consistent with a reciprocal translocation as the cause of the difference in the size of the HTS1-containing chromosome among the Tox2+ isolates studied here. Physical mapping of the 3.5-Mb chromosome of SB111 that contains HTS1 using rare-cutting restriction enzymes and engineered restriction sites was used to map the chromosome location of the two copies of HTS1 and the three copies of TOXC. The results indicate that TOX2 is a complex locus that extends over more than 500 kb. The capacity to produce HC-toxin did not evolve by any single, simple mechanism.

Amino Acid Isomerases↗

PubMed1989

The alpha 3 beta 3 complex, the catalytic core of F1-ATPase.

The alpha 3 beta 3 complex was reconstituted from alpha and beta subunits of the thermophilic bacterium PS3 F1-ATPase (TF1) and then isolated. It is less stable at high and low temperatures than TF1, and the complex dissociates into subunits during native polyacrylamide gel electrophoresis. The alpha 3 beta 3 complex has about 20% of the ATPase activity of TF1. Its enzymic properties are similar to those of the native TF1, exhibiting similar cooperative kinetics as a function of ATP concentration, similar substrate specificity for nucleotide triphosphates, and the presence of two peaks in its temperature-activity profile. Differing from TF1, the ATPase activity of the alpha 3 beta 3 complex is insensitive to N3- inhibition, its divalent cation specificity is less stringent, and its optimum pH shifts to the alkaline side. The addition of the gamma subunit to the alpha 3 beta 3 complex leads to the formation of the alpha 3 beta 3 gamma complex, indicating that the alpha 3 beta 3 complex is an intermediate in the process of assembly of the holoenzyme from each subunit. These results definitely show that the essential structure for eliciting the ATPase activity of F1-ATPase is trimeric alpha beta pairs and that the kinetic cooperativity of the F1-ATPase is an inherent property of this trimeric structure but is not due to the presence of single-copy subunits. In this sense, the alpha 3 beta 3 complex is the catalytic core of F1-ATPase.

Bacteria↗

PubMed2005

Molecular structure of a 9-MDa icosahedral pyruvate dehydrogenase subcomplex containing the E2 and E3 enzymes using cryoelectron microscopy.

The pyruvate dehydrogenase multienzyme complexes are among the largest multifunctional catalytic machines in cells, catalyzing the production of acetyl CoA from pyruvate. We have previously reported the molecular architecture of an 11-MDa subcomplex comprising the 60-mer icosahedral dihydrolipoyl acetyltransferase (E2) decorated with 60 copies of the heterotetrameric (alpha(2)beta(2)) 153-kDa pyruvate decarboxylase (E1) from Bacillus stearothermophilus (Milne, J. L. S., Shi, D., Rosenthal, P. B., Sunshine, J. S., Domingo, G. J., Wu, X., Brooks, B. R., Perham, R. N., Henderson, R., and Subramaniam, S. (2002) EMBO J. 21, 5587-5598). An annular gap of approximately 90 A separates the acetyltransferase catalytic domains of the E2 from an outer shell formed of E1 tetramers. Using cryoelectron microscopy, we present here a three-dimensional reconstruction of the E2 core decorated with 60 copies of the homodimeric 100-kDa dihydrolipoyl dehydrogenase (E3). The E2E3 complex has a similar annular gap of approximately 75 A between the inner icosahedral assembly of acetyltransferase domains and the outer shell of E3 homodimers. Automated fitting of the E3 coordinates into the map suggests excellent correspondence between the density of the outer shell map and the positions of the two best fitting orientations of E3. As in the case of E1 in the E1E2 complex, the central 2-fold axis of the E3 homodimer is roughly oriented along the periphery of the shell, making the active sites of the enzyme accessible from the annular gap between the E2 core and the outer shell. The similarities in architecture of the E1E2 and E2E3 complexes indicate fundamental similarities in the mechanism of active site coupling involved in the two key stages requiring motion of the swinging lipoyl domain across the annular gap, namely the synthesis of acetyl CoA and regeneration of the dithiolane ring of the lipoyl domain.

Binding Sites↗

PubMed1996

Specificity of ribonucleoprotein interaction determined by RNA folding during complex formulation.

Many proteins involved in pre-mRNA processing contain one or more copies of a 70-90-amino-acid alphabeta module called the ribonucleoprotein domain. RNA maturation depends on the specific recognition by ribonucleoproteins of RNA elements within pre-mRNAs and small nuclear RNAs. The human U1A protein binds an RNA hairpin during splicing, and regulates its own expression by binding an internal loop in the 3'-untranslated region of its pre-mRNA, preventing polyadenylation. Here we report the nuclear magnetic resonance structure of the complex between the regulatory element of the U1A 3'-untranslated region (UTR) and the U1A protein RNA-binding domain. Specific intermolecular recognition requires the interaction of the variable loops of the ribonucleoprotein domain with the well-structured helical regions of the RNA. Formation of the complex then orders the flexible RNA single-stranded loop against the protein beta-sheet surface, and reorganizes the carboxy-terminal region of the protein to maximize surface complementarity and functional group recognition.

Amino Acid Sequence↗

PubMed1997

A novel pathogenic taxon of the Mycobacterium tuberculosis complex, Canetti: characterization of an exceptional isolate from Africa.

In an attempt to characterize an unusual mycobacterial strain isolated from a 2-year-old Somali patient with lymphadenitis, we applied various molecular methods not previously used for the taxonomic classification of mycobacteria. This isolate, designated So93, did not differ from Mycobacterium tuberculosis in the biochemical tests and in its 16S rRNA sequence, but produced smooth and glossy colonies, which is highly exceptional for this species. This smooth phenotype was unstable and switched nonreversibly to a rough colony morphology with a low frequency. The two colony types were equally virulent for the guinea pig, exhibiting characteristic tuberculous disease. Both morphotypes had shorter generation times than the M. tuberculosis reference laboratory strain H37Rv and clinical isolates of M. tuberculosis and Mycobacterium bovis. Furthermore, the So93 isolate differed from all M. tuberculosis complex strains described thus far by having only a single copy of insertion sequence IS1081, an unusual composition of the direct repeat cluster, and a characteristic phenolic glycolipid and lipooligosaccharide. This glycolipid had previously been observed only in a smooth isolate of M. tuberculosis obtained in 1969 by Canetti in France. Analysis of the Canetti strain showed that it shared virtually all genetic properties characteristic of So93, distinguishing these two strains from the known M. tuberculosis complex taxa, M. tuberculosis, Mycobacterium africanum, M. bovis, and Mycobacterium microti. The natural reservoir, host range, and mode of transmission of the group of bacteria described in this paper are presently unknown. This study, partly based on not previously used molecular criteria, supports the idea that the established members within the M. tuberculosis complex and the newly described Canetti grouping should be regarded as a single species, which likely will be designated "M. tuberculosis".

Animals↗

PubMed2004

Stoichiometry of LHCI antenna polypeptides and characterization of gap and linker pigments in higher plants Photosystem I.

We report on the results obtained by measuring the stoichiometry of antenna polypeptides in Photosystem I (PSI) from Arabidopsis thaliana. This analysis was performed by quantification of Coomassie blue binding to individual LHCI polypeptides, fractionation by SDS/PAGE, and by the use of recombinant light harvesting complex of Photosystem I (Lhca) holoproteins as a standard reference. Our results show that a single copy of each Lhca1-4 polypeptide is present in Photosystem I. This is in agreement with the recent structural data on PSI-LHCI complex [Ben Shem, A., Frolow, F. and Nelson, N. (2003) Nature, 426, 630-635]. The discrepancy from earlier estimations based on pigment binding and yielding two copies of each LHCI polypeptide per PSI, is explained by the presence of 'gap' and 'linker' chlorophylls bound at the interface between PSI core and LHCI. We showed that these chlorophylls are lost when LHCI is detached from the PSI core moiety by detergent treatment and that gap and linker chlorophylls are both Chl a and Chl b. Carotenoid molecules are also found at this interface between LHCI and PSI core. Similar experiments, performed on PSII supercomplexes, showed that dissociation into individual pigment-proteins did not produce a significant loss of pigments, suggesting that gap and linker chlorophylls are a peculiar feature of Photosystem I.

Arabidopsis↗

PubMed2005

Three copies of the ATP2 gene are arranged in tandem on chromosome X in the yeast Saccharomyces cerevisiae.

We previously reported that there were three copies of ATP1 coding for F1-alpha and two copies of ATP3 coding for F1-gamma on the left and right arm of chromosome II, respectively. In this study, we present evidence that there are three closely linked copies of ATP2 encoding the beta subunit of the F1F0-ATPase complex on the right arm of chromosome X in several laboratory strains, including Saccharomyces cerevisiae strain S288C, although it was reported by the yeast genome project that ATP2 is a single-copy gene. Chromosome X fragmentation, long-PCR, chromosome-walking and ATP2-disruption analysis using haploid wild-type strains and prime clone 70645 showed that the three copies of ATP2 are present on the right arm of chromosome X, like those of ATP1 on chromosome II. Each was estimated to be approximately 4 kb apart. We designated the ATP2 proximal to the centromere as ATP2a, the middle one as ATP2b and the distal one as ATP2c. The region containing the three ATP2s is composed of two repeated units of approximately 7 kb; that is, both ends (ATP2a, ATP2c) accompanying the ATP2-neighboring ORFs are the same. A part of YJR119c, YJR120w, YJR122w (CAF17) and YJR123w (RP55), which were reported by the yeast genome project, are contained in the ATP2 repeated units; and the middle ATP2 of the three ATP2s, ATP2b, is located between the two repeated units. Expression of all three copies of ATP2 (ATP2a, ATP2b, ATP2c) was confirmed because a single or double ATP2-disruptant could grow on glycerol, but a triple ATP2-disruptant could not. In addition, of the three copies of ATP1 and ATP2, even if only one copy of the ATP1 and ATP2 genes remained, the cells grew on glycerol.

Blotting, Southern↗

PubMed2006

Involvement of specific COPI subunits in protein sorting from the late endosome to the vacuole in yeast.

Although COPI function on the early secretory pathway in eukaryotes is well established, earlier studies also proposed a nonconventional role for this coat complex in endocytosis in mammalian cells. Here we present results that suggest an involvement for specific COPI subunits in the late steps of endosomal protein sorting in Saccharomyces cerevisiae. First, we found that carboxypeptidase Y (CPY) was partially missorted to the cell surface in certain mutants of the COPIB subcomplex (COPIb; Sec27, Sec28, and possibly Sec33), which indicates an impairment in endosomal transport. Second, integral membrane proteins destined for the vacuolar lumen (i.e., carboxypeptidase S [CPS1]; Fur4, Ste2, and Ste3) accumulated at an aberrant late endosomal compartment in these mutants. The observed phenotypes for COPIb mutants resemble those of class E vacuolar protein sorting (vps) mutants that are impaired in multivesicular body (MVB) protein sorting and biogenesis. Third, we observed physical interactions and colocalization between COPIb subunits and an MVB-associated protein, Vps27. Together, our findings suggest that certain COPI subunits could have a direct role in vacuolar protein sorting to the MVB compartment.

Cathepsin A↗

PubMed1990

Control of replication of plasmid R1: formation of an initial transient complex is rate-limiting for antisense RNA--target RNA pairing.

The replication frequency of plasmid R1 is determined by the availability of the initiator protein RepA. Synthesis of RepA is negatively controlled by an antisense RNA, CopA, which forms a duplex with the upstream region of the RepA mRNA, CopT. We have previously shown that the in vitro formation of the CopA-CopT duplex follows second-order kinetics and occurs in at least two steps. The first step is the formation of a transient (kissing) complex, which is subsequently converted to a persistent duplex. Here, we investigate the details of the reaction scheme and determine the rate constants of the pathway from the free RNAs to the complete duplex. Using a shortened CopA RNA (CopI) we have been able to determine the association and dissociation rate constants (k1,k-1) for the kissing complex (which are inferred to be the same for CopI-T and CopA-T), and measured the hybridization rate constant k2 (for CopA-T k2 is at least 1000-fold greater than for CopI-T). The analysis of CopA derivatives of mutant and wild-type origin shows that the rate of formation of the kissing complex is rate-limiting for the overall pairing reaction between CopA and CopT, both in vitro and in vivo. The biological implications of the kinetically irreversible RNA-RNA binding reaction scheme are discussed.

DNA Mutational Analysis↗

PubMed1986

Sequence complexity of polyadenylate ribonucleic acid in El mouse brain.

To elucidate the sequence complexity of polyadenylate messenger RNA [poly(A+)mRNA] regarding the seizure-susceptible El mouse brain, the proportion of complexity was measured by saturation hybridization using a single-copy DNA (scDNA) with excess RNA. At saturation, 3.81, 3.85 and 4.00% of scDNA hybridized with polysomal poly(A+)mRNAs of El(+), El(O) which had not been convulsed, and ddY (nonsusceptible) mice, respectively. The additive hybridization of a mixture of El(+) and ddY mouse mRNAs was 4.04%. The results suggest that there are considerable overlapping sets within the poly(A+)mRNA sequences between the ddY and El mice, but the complexity of ddY mice mRNA is slightly larger than that of the El mice, whereas poly(A+) heterogeneous nuclear RNA (hnRNA) hybridized with about 18% of scDNA in three strains of mice.

Animals↗

PubMed2005

Copy and recall performance of 6-8-year-old children after standard vs. Step-by-step administration of the Rey-Osterrieth complex figure.

The Rey-Osterrieth Complex Figure (ROCF; Rey 1941; Osterrieth, 1944) is frequently used in the neuropsychological assessment of children and adults. The present study was designed, in part, to examine the impact of providing organizational scaffolding to young children being tested with the ROCF. To this end, 6-, 7-, and 8-year-old children were administered the test either in the standard fashion, or using a format in which the 18 key elements of the figure were introduced sequentially. Participants included 132 children who were randomly assigned to the standard or step-by-step administration groups. Significantly higher accuracy and organization scores for both copy and recall were seen with the step-by-step format than with the standard format, even though children in the step-by-step condition took less time to execute their drawings. Retention of encoded information was not affected by age or testing format. The fact that 6-year-olds in the step-by-step condition performed as well as, or better than, 8-year-olds in the standard condition suggests that the primary problem young children experience with the ROCF lies with organizational strategy formation. Advantages of using the Step-by-step ROCF in clinical practice are discussed.

Child↗

PubMed2002

Isolation of A/D and C genome specific dispersed and clustered repetitive DNA sequences from Avena sativa.

DNA gel-blot and in situ hybridization with genome-specific repeated sequences have proven to be valuable tools in analyzing genome structure and relationships in species with complex allopolyploid genomes such as hexaploid oat (Avena sativa L., 2n = 6x = 42; AACCDD genome). In this report, we describe a systematic approach for isolating genome-, chromosome-, and region-specific repeated and low-copy DNA sequences from oat that can presumably be applied to any complex genome species. Genome-specific DNA sequences were first identified in a random set of A. sativa genomic DNA cosmid clones by gel-blot hybridization using labeled genomic DNA from different Avena species. Because no repetitive sequences were identified that could distinguish between the A and D gneomes, sequences specific to these two genomes are refereed to as A/D genome specific. A/D or C genome specific DNA subfragments were used as screening probes to identify additional genome-specific cosmid clones in the A. sativa genomic library. We identified clustered and dispersed repetitive DNA elements for the A/D and C genomes that could be used as cytogenetic markers for discrimination of the various oat chromosomes. Some analyzed cosmids appeared to be composed entirely of genome-specific elements, whereas others represented regions with genome- and non-specific repeated sequences with interspersed low-copy DNA sequences. Thus, genome-specific hybridization analysis of restriction digests of random and selected A. sativa cosmids also provides insight into the sequence organization of the oat genome.

Avena↗

PubMed2005

Cognitive deficits in unaffected first-degree relatives of schizophrenia patients: a meta-analytic review of putative endophenotypes.

Cognitive deficits may index genetic liability for schizophrenia and are candidate endophenotypes for the illness. In order to compare the degree of sensitivity among cognitive tasks to group differences between healthy relatives and controls and the influence of moderator variables, this review reports mean effect sizes for 43 cognitive test scores from 58 studies of cognitive performance in the unaffected adult relatives of schizophrenia patients. Results indicate reliable relative-control differences, in the small to medium effect size range, over a diverse array of tasks, with the largest effect sizes seen in complex versions of continuous performance tasks, auditory verbal learning, design copy tests, and category fluency. Three study design features were found to have significant effects on overall effect size magnitude: groups unmatched on education, groups unmatched on age, and asymmetric psychiatric exclusion criteria. After excluding studies with the latter 2 design features, reliable performance differences were still observed over a smaller subset of cognitive test variables, with the largest effect sizes seen in Trails B (d = 0.50) and performance measures from both simple (d = 0.56) and complex (d = 0.60-0.66) versions of continuous performance tasks. Four of the 6 largest effect sizes reflect tasks with high executive control demands in common, such as working memory demands, set shifting, and inhibition of prepotent responses. Cognitive deficits, particularly those tapping such executive control functions, should continue to prove valuable as endophenotypes of interest in the search for specific genetic factors related to schizophrenia.

Cognition Disorders↗

PubMed1999

Genome-wide analysis of DNA copy-number changes using cDNA microarrays.

Gene amplifications and deletions frequently contribute to tumorigenesis. Characterization of these DNA copy-number changes is important for both the basic understanding of cancer and its diagnosis. Comparative genomic hybridization (CGH) was developed to survey DNA copy-number variations across a whole genome. With CGH, differentially labelled test and reference genomic DNAs are co-hybridized to normal metaphase chromosomes, and fluorescence ratios along the length of chromosomes provide a cytogenetic representation of DNA copy-number variation. CGH, however, has a limited ( approximately 20 Mb) mapping resolution, and higher-resolution techniques, such as fluorescence in situ hybridization (FISH), are prohibitively labour-intensive on a genomic scale. Array-based CGH, in which fluorescence ratios at arrayed DNA elements provide a locus-by-locus measure of DNA copy-number variation, represents another means of achieving increased mapping resolution. Published array CGH methods have relied on large genomic clone (for example BAC) array targets and have covered only a small fraction of the human genome. cDNAs representing over 30,000 radiation-hybrid (RH)-mapped human genes provide an alternative and readily available genomic resource for mapping DNA copy-number changes. Although cDNA microarrays have been used extensively to characterize variation in human gene expression, human genomic DNA is a far more complex mixture than the mRNA representation of human cells. Therefore, analysis of DNA copy-number variation using cDNA microarrays would require a sensitivity of detection an order of magnitude greater than has been routinely reported. We describe here a cDNA microarray-based CGH method, and its application to DNA copy-number variation analysis in breast cancer cell lines and tumours. Using this assay, we were able to identify gene amplifications and deletions genome-wide and with high resolution, and compare alterations in DNA copy number and gene expression.

Chromosomes, Human, Pair 17↗

PubMed1994

Isolation of region specific single-copy probes from human chromosome 1q23-->1q25.

Single-copy sequences of chromosome bands 1q23-->1q25 were enriched by subtractive hybridization of digoxigenin oligonucleotide-labeled DNA from a somatic cell hybrid containing human chromosome 1 with DNA from a somatic cell hybrid containing a deleted human chromosome 1, del(1)(q23q25). These sequences were purified with an immobilized anti-digoxigenin antibody, amplified by polymerase chain reaction (PCR) and cloned. The majority of clones contained single-copy sequences, thus allowing direct screening of human genomic DNA. With pools of probes complex hybridization patterns as well as differences in hybridization patterns between genomes were observed in Southern blotting experiments. Nine clones containing independent single-copy sequences from chromosome bands 1q23-->1q25 were isolated and sequenced to generate sequence-tagged sites (STSs). Using PCR, region specific genomic clones containing large inserts were identified in human genomic lambda phage and cosmid libraries. Thus, region specific genomic probes generated by genomic difference cloning are useful for identifying deletions and rearrangements, for generating STSs and for isolating genomic clones containing large inserts of a particular chromosomal region.

Base Sequence↗

PubMed2002

Composition of the lambda plasmid heritable replication complex.

Previous studies indicated during replication of plasmids derived from bacteriophage lambda (the so-called lambda plasmids), that, once assembled, replication complex can be inherited by one of the two daughter plasmid copies after each replication round, and may function in subsequent replication rounds. It seems that similar processes occur during replication of other DNA molecules, including chromosomes of the yeast Saccharomyces cerevisiae. However, apart from some suggestions based on genetic experiments, composition of the lambda heritable replication complex remains unknown. In amino acid-starved Escherichia coli relA mutants, replication of lambda plasmid DNA is carried out exclusively by the heritable replication complex as assembly of new complexes is impaired due to inhibition of protein synthesis. Here, using a procedure based on in vivo cross-linking, cell lysis, immunoprecipitation with specific sera, de-cross-linking and PCR analysis, we demonstrate that the lambda heritable replication complex consists of O, P, DnaB and, perhaps surprisingly, DnaK proteins.

Base Sequence↗

PubMed1992

The contribution of constructional accuracy and organizational strategy to nonverbal recall in schizophrenia and chronic alcoholism.

The Rey-Osterrieth complex figure was used to assess the separate influences of the constructional accuracy and the organizational strategy employed while copying the figure on the later, incidental recall of the figure. We tested a model, which hypothesized that subjects who copied the main framework of the figure holistically would be more likely to achieve good copy accuracy scores and to reproduce the figure more accurately at recall than subjects who used a piecemeal approach during copy. Subjects included 68 detoxified, chronic alcoholics (ALC), 28 patients with schizophrenia (SZ), and 69 normal control subjects (NCS). The results showed that the ALC and the SZ groups, on average, had lower accuracy and strategy scores at copy than did the NCS group, and furthermore, that the combined contributions of copy accuracy and copy strategy accounted for group differences at recall. A path analysis revealed that, for all three groups, copy strategy had a significant direct effect on copy accuracy. Moreover, copy accuracy and copy strategy made independent contributions to recall accuracy within the ALC and NCS groups; by contrast, within the SZ group, copy strategy made an independent contribution to recall performance but copy accuracy did not. These results suggest that (1) organizational strategy can influence constructional accuracy at both copy and recall; (2) copy accuracy and strategy have the potential to influence recall independently; and (3) the recall deficit in ALC could be attributed to abnormalities in both accuracy and strategy at copy, whereas in SZ it could be attributed only to strategy abnormalities. The deficits observed on the complex figure test in the ALC and SZ were primarily nonmnemonic and were related to ability in figure construction and organizational strategy.

Adult↗

PubMed2002

Rapid-cycle PCR and fluorimetry for detection of mycobacteria.

In this study we used LightCycler PCR amplification and product detection by fluorescence resonance energy transfer probes to identify mycobacteria and differentiate between Mycobacterium tuberculosis complex, Mycobacterium avium, and other nontuberculous mycobacteria. Targeting the 16S rRNA gene, three different probes specific for mycobacteria, M. tuberculosis complex, and M. avium were constructed. As few as five genome copies of target nucleic acid were detected by the probes, illustrating the high sensitivity of the system. All 33 mycobacterial species tested but none of the closely related actinomycetes and other bacteria produced a specific fluorescence signal. A specificity of 100% was also demonstrated for the M. tuberculosis complex-specific probe and the M. avium-specific probe. Within 45 min, the LightCycler method correctly detected mycobacteria and specifically identified M. tuberculosis complex and M. avium without any post-PCR sample manipulation. In view of future clinical studies, we also constructed and tested an internal control which could be used to assure successful amplification and detection of mycobacteria. Monitoring of PCR inhibition will be essential for evaluation of this system for direct detection of mycobacteria in clinical specimens. Finally, we tested our system on sputum seeded with mycobacteria and were able to detect as few as 10 organisms. At present, this system is the fastest available method for identification and differentiation of mycobacteria from culture-positive specimens and offers an excellent alternative to previously established nucleic acid amplification-based techniques for the diagnostic mycobacterial laboratory.

Bacterial Typing Techniques↗