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PubMed1999

A novel human gene encoding an F-box/WD40 containing protein maps in the SHFM3 critical region on 10q24.

We report the cloning and characterization of a new human gene, Dactylin, encoding a novel member of the F-box/WD40 protein family. The Dactylin gene comprises nine exons distributed in more than 85 kb of genomic DNA and encoding a protein with four WD40 repeats and an F-box motif. Northern blot analysis demonstrates a single 2.8 kb transcript in brain, kidney, lung and liver. FISH hybridization localized Dactylin to 10q24.3. Using an Msc I SNP identified in the first exon of the gene, we were able to assign Dactylin within the critical region for Split Hand Split Foot malformation (SHFM3) that has been mapped to 10q24. The SHFM3 phenotype includes absence or hypoplasia of the central digital rays, a deep median cleft and syndactyly of the remaining digits. Recent studies have demonstrated the importance of F-box/WD40 proteins in the regulation of developmental processes, by a mechanism of specific ubiquitinization and subsequent proteolysis of target proteins belonging to the Wnt, Hh and NF-kappaB signaling pathways. The chromosomal location of Dactylin and its putative function as an F-box/WD40 repeat protein, likely to be involved in key signaling pathways crucial for normal limb development, make it a promising candidate gene for SHFM3.

Amino Acid Sequence↗
PubMed2006

Effect of changes in food consistency on NADH-ubiquinone oxidoreductase activity and levels of mRNA for ND1, 51kDa, 75kDa and myosin heavy chain isoforms in two different portions of rat masseter muscle.

We investigated the effect of a change in food consistency on properties of the masseter muscle in 3-week-old rats fed a soft diet for 9 weeks (Group S) and fed a soft diet for 5 weeks followed by a hard diet for 4 weeks (Group S-H). The NADH-O2 oxidoreductase activity, levels of mRNAs transcribed from genes encoding NADH-ubiquinone oxidoreductase (Complex I: ND1, 51kDa, and 75kDa) and myosin heavy chain (MyHC) isoforms and the phenotype of the muscle fibers were measured in the superficial and deep portions of the muscle. In the period from 8 weeks to 12 weeks of age, NADH-O2 oxidoreductase enzyme activity in both the superficial and deep portions of the muscle showed similar patterns in Group S and Group S-H. In contrast, the ND1, 51kDa and 75kDa mRNA levels in the superficial and deep portions of the masseter muscle in the Group S-H were higher than those of Group S in the 12-week-old rats, except for the 51kDa mRNA in the superficial portion of the masseter muscle. MyHC-IIa and MyHC-IId/x mRNA levels in the superficial portion of the masseter muscle were higher in the Group S-H than in the Group S. These observations suggest that short-term feeding stress such as the transition from a soft diet to a hard diet causes changes in oxidative metabolism, in mRNA levels for the Complex I components ND1 and 75kDa, and the mRNA levels for the MyHC isoforms IIa and IId/x in the superficial portion of rat masseter muscle, but no changes in the composition of muscle fiber types.

Animals↗
PubMed1985

Decreased cerebellar 3',5'-cyclic guanosine monophosphate levels and insensitivity to harmaline in the genetically dystonic rat (dt).

The dystonic rat (dt) is an autosomal recessive mutant displaying a complex motor syndrome that includes sustained axial twisting movements. The syndrome is correlated with increased glutamic acid decarboxylase activity in the deep cerebellar nuclei and increased cerebellar norepinephrine levels in comparison with phenotypically normal littermates. Biochemical, behavioral, and anatomical techniques were used to investigate the possibility that the abnormalities noted in the cerebellum of the dt rat were indicative of altered function of the major projection neurons of the cerebellar cortex, the Purkinje cells. Phenotypically normal rats showed tremor in response to harmaline, a drug that acts on the inferior olive to produce bursting in the climbing fiber pathway. Dystonic rats were insensitive to the effects of harmaline but did respond to oxotremorine. Levels of the cyclic nucleotide 3',5'-cyclic guanosine monophosphate, a biochemical marker for Purkinje cells, increased in response to harmaline in normal rats but were significantly lower in dystonic rats under both basal and harmaline-stimulated conditions. Purkinje cell soma size was reduced in the dystonic rats but no other morphological correlates of the behavioral or biochemical deficits were noted. Taken together with other observations on this mutant, the results suggest an impairment in the cerebellum or in its connections with lower brainstem and spinal cord sites.

Alkaloids↗
PubMed1990

Phenotypic modulation in sub-populations of human articular chondrocytes in vitro.

Human articular cartilage has been separated into surface (approx. 15% of tissue depth) and deep zones (remaining tissue) and the constituent chondrocytes released by enzymic digestion. Subsequent culture either as a low density monolayer or as a suspension over agarose revealed distinct morphological and synthetic behaviour in the two populations. Whilst in monolayer these morphological differences disappeared with time in culture, over agarose they remained. Surface zone cells formed two types of cell cluster; one that was highly cellular with little extracellular matrix, and the other less frequent, which formed copious amounts of fibrillar matrix. Both types of cluster were surrounded by a layer of flattened chondrocytes. In contrast, deep cells formed a single cluster type that lacked a surrounding cell layer, but formed large amounts of sparse cartilage-like matrix and comprised morphologically typical chondrocytes. In monolayer, both populations gradually ceased to synthesise cartilage matrix components with the exception of link protein. In suspension, whilst the chondrogenic phenotype per se was preserved, there was, nevertheless, a loss in qualitative synthetic heterogeneity, which exists between surface and deep cells, that was not accompanied by changes in the differential rate of 35S incorporation into proteoglycan. Under these conditions, surface cells that normally do not synthesise keratan sulphate initiated de novo synthesis of this glycosaminoglycan. Consequently, it appears that the observed modulation in synthetic ability of the cell sub-populations is independent of the cluster morphology, which, once established, remains constant throughout the culture period.

Cartilage, Articular↗
PubMed2007

Shewanella psychrophila sp. nov. and Shewanella piezotolerans sp. nov., isolated from west Pacific deep-sea sediment.

Two Shewanella-like bacterial strains, WP2(T) and WP3(T), which were isolated from west Pacific deep-sea sediment, were studied to determine their taxonomic position. Cells of the two bacteria were facultatively anaerobic, Gram-negative rods and motile by means of a single polar flagellum. Strain WP2(T) was psychrophilic, growing optimally at about 10-15 degrees C, whereas strain WP3(T) was psychrotolerant, growing optimally at 15-20 degrees C. The two strains grew in the pressure range 0.1-50 MPa, with optimal growth at 20 MPa. Strain WP3(T) was able to use nitrate, fumarate, trimethylamine N-oxide (TMAO), DMSO and insoluble Fe(III) as terminal electron acceptors during anaerobic growth, whereas strain WP2(T) was able to use only nitrate, TMAO and DMSO. The 16S rRNA gene sequences of strains WP2(T) and WP3(T) were 97 % identical, and showed highest similarity (97 %) to those of Shewanella fidelis KMM 3589 and Shewanella benthica ATCC 43992(T), respectively. The gyrB gene sequences of strains WP2(T)and WP3 (T) were also determined, and showed highest similarity to those of Shewanella violacea JCM 10179(T) (90 %) and Shewanella sairae SM2-1(T) (87 %), respectively. Contrary to the 16S rRNA gene sequence results, the phylogeny based on gyrB gene sequence analysis placed strain WP2(T), S. violacea and S. benthica in one group, while strain WP3(T) grouped with S. fidelis and S. sairae. DNA-DNA hybridization experiments supported the placement of strain WP2(T) with S. violacea and S. benthica. Phylogenetic evidence, together with DNA-DNA relatedness and phenotypic characteristics, indicated that the two new strains represented two novel deep-sea Shewanella species. The names Shewanella psychrophila sp. nov. (type strain WP2(T)=JCM 13876(T)=CGMCC 1.6159(T)) and Shewanella piezotolerans (type strain WP3(T)=JCM 13877(T)=CGMCC 1.6160(T)) are proposed.

Bacterial Typing Techniques↗
PubMed2004

Phenotypic switching and beta-N-acetylhexosaminidase activity of the pathogenic yeast Trichosporon asahii.

The pathogenic yeast Trichosporon asahii is the major causative agent of deep-seated trichosporonosis in immunocompromised patients. Although infection by this microorganism is becoming increasingly frequent, information related to its pathogenicity and virulence factors is still limited. Therefore, we investigated phenotypic switching in colony morphology, and the production of extracellular enzymes as a virulence factor. Sixty-one clinical isolates of T. asahii produced four different morphological types on Sabouraud dextrose agar (SDA): 69% WF (white farinose), 18% WP (white pustular), 10% Y (yellowish white), and 3% WC (white cerebriform). Strains of the three major types (WF, WP, and Y) produced two to five colony types when cultured on SDA at 37 C. The frequency of switching between colony types was 10(-2) to 10(-4), as in Candida albicans and Cryptococcus neoformans. Notably, most of the colonies switched to the smooth (S) type irreversibly, at frequencies of 10(-2) to 10(-3). No secreted aspartic proteinase or phospholipase activity was detected in T. asahii, while beta-N-acetylhexosaminidase activity, which catalyzes the hydrolysis of terminal nonreducing N-acetyl-D-hexosamine residues in N-acetyl-beta-D-hexosaminides, was found. Furthermore, enzymatic activity of the S type was significantly greater than that of the parent type in all strains. No other clinically relevant Trichosporon species (T. mucoides, T. inkin, and T. ovoides ) produced this enzyme. These results provide basal information for understanding the pathogenic potential of T. asahii.

Culture Media↗
PubMed2006

Arrest of flagellum morphogenesis with fibrous sheath immaturity of human spermatozoa.

Morphogenesis of the mammalian sperm flagellum is characterized by the assembly of axonemal and peri-axonemal structures. The incorporation of mitochondria into the flagellum results from complex cellular events, including flagellum compartmentalization and membrane and organelle reorganization. These events are striking in the annulus, which progressively relocates from the neck to the principal piece of the flagellum. This study presents a human sperm phenotype with failure of the annulus relocation, absence of mitochondrial sheath and a fibrous sheath at intermediate step of assembly. The sperm nucleus was fully condensed but with deep invaginations engulfing the acrosome. The distal pole of some mitochondria exhibited an unusual dense substance. This rare human sperm phenotype was found in a consanguineous patient, suggesting a genetic origin. These anomalies raise the question of the mechanisms that lead to impairment of both the annulus relocation and the deposit of proteins on the fibrous sheath during spermiogenesis.

Adult↗
PubMed2006

Clinical and electrophysiological aspects of Charcot-Marie-Tooth disease.

Charcot-Marie-Tooth disease (CMT) is a genetically heterogeneous group of disorders sharing the same clinical phenotype, characterized by distal limb muscle wasting and weakness, usually with skeletal deformities, distal sensory loss, and abnormalities of deep tendon reflexes. Mutations of genes involved in different functions eventually lead to a length-dependent axonal degeneration, which is the likely basis of the distal predominance of the CMT phenotype. Nerve conduction studies are important for classification, diagnosis, and understanding of pathophysiology. The subdivision into demyelinating CMT1 and axonal CMT2 types was a milestone and is still valid for the majority of patients. However, exceptions to this partition are increasing. Intermediate conduction velocities are often found in males with X-linked CMT (CMTX), and different intermediate CMT types have been identified. Moreover, for some genes, different mutations may result either in demyelinating CMT with slow conduction, or in axonal CMT. Nerve conduction slowing is uniform and diffuse in the most common CMT1A associated with the 17p12 duplication, whereas it is often asymmetric and nonhomogeneous in CMTX, sometimes rendering difficult the differential diagnosis with acquired inflammatory neuropathies. The demyelinating recessive forms, termed CMT4, usually have early onset and run a more severe course than the dominant types. Pure motor CMT types are now classified as distal hereditary motor neuronopathy. The diagnostic approach to the identification of the CMT subtype is complex and cannot be based on the clinical phenotype alone, as different forms are often clinically indistinguishable. However, there are features that may be of help in addressing molecular investigation in a single patient. Late onset, prominent or peculiar sensory manifestations, autonomic nervous system dysfunction, cranial nerve involvement, upper limb predominance, subclinical central nervous system abnormalities, severe scoliosis, early-onset glaucoma, neutropenia are findings helpful for diagnosis.

Charcot-Marie-Tooth Disease↗
PubMed2005

Disruption of cerebellar granule cell development in the Pax6 mutant, Sey mouse.

The transcriptional regulator Pax6 is expressed in cerebellar granule cells and a mutation in that gene (Sey) has been shown to affect cerebellar development. We have defined novel phenotypes in the Sey/Sey cerebellum, indicating that the mutation of Pax6 alters granule cell behavior in vitro and also the interaction between granule cells and Purkinje cells in vivo. In culture, Sey/Sey granule cell precursors show the following abnormal phenotypes: enhanced proliferation, increased apoptotic cell death, and decreased number of morphologically differentiating beta-III tubulin-positive cells. There is an overlap in the populations of Sey/Sey cells that express markers for proliferation and neuronal differentiation indicating an abnormality in the transition between these states in granule cells. In vivo, Purkinje cell ectopias were found deep in the cerebellum and extending into the inferior colliculus. Coincident with this, Purkinje cell phenotype was the alteration in the pattern and levels of Reelin expression in granule cells of the external germinal layer (EGL). The finding of increased staining for Disabled-1, a signaling pathway intermediary that is normally downregulated by a Reelin signal, throughout the Purkinje cell population suggests that in the Sey/Sey cerebellum there is a disruption in Reelin signaling from the EGL to Purkinje cells. These findings suggest that Pax6 is critical for the proper differentiation of granule cells and their communication with developing Purkinje cells. Thus, through its guidance of granule cell development, Pax6 also has a strong influence on many of the cellular programs that guide the morphogenesis of the entire cerebellum.

Animals↗
PubMed1998

Behavioral phenotype of Smith-Magenis syndrome (del 17p11.2).

Smith-Magenis syndrome (SMS) is a distinct and clinically recognizable multiple congenital anomaly (MCA) and mental retardation syndrome caused by an interstitial deletion of chromosome 17 p11.2. The phenotype of SMS has been well described and includes: a characteristic pattern of physical features; a hoarse, deep voice; speech delay with or without associated hearing loss; signs of peripheral neuropathy; variable levels of mental retardation; and neurobehavioral problems. Although self-injury and sleep disturbance are major problems in SMS, studies are limited on the behavioral phenotype of SMS. This report reviews the current state of knowledge about SMS and presents new data based on syndrome-specific observations by the authors' longitudinal experience working with SMS, specifically related to the behavioral aspects of SMS. This information should have relevance for parents, clinicians, geneticists, and educators involved in the care of individuals with SMS.

Abnormalities, Multiple↗
PubMed2005

An integrated spinal cord-hindlimbs preparation for studying the role of intrinsic properties in somatosensory information processing.

Several studies performed using the slice in vitro technique have shown that spinal cord neurons display specialized intrinsic electrophysiological properties. However, the actual role of intrinsic properties in somatosensory processing remains unclear, mainly due to the impossibility to generate natural sensory inputs in spinal cord slices. Here, we show an integrated spinal cord-hindlimbs preparation of juvenile turtles that has the advantages of in vitro approaches and still enables natural stimulation. By making patch-clamp whole-cell recordings of both superficial and deep dorsal horn neurons in the integrated preparation, we found similar electrophysiological phenotypes as those observed in slices. Most of the cells responded to natural stimuli, had large receptive fields and were classified as wide-dynamic range neurons. Both low-threshold spikes and plateau potentials interacted with naturally evoked sensory inputs, generating complex dynamics. Furthermore, we found that the activity of the spinal cord network induced by natural stimulation modulated the excitability of plateau-generating cells. This effect was mimicked by bath application of cis-(+/-)-1-aminocyclopentane-1,3-dicarboxylic acid (ACPD), a group I glutamate metabotropic receptor agonist. Our results show that the spinal cord-hindlimbs preparation represents a valuable model to study the contribution of intrinsic properties to early stages of somatosensory information processing.

Animals↗
PubMed2003

Dialister invisus sp. nov., isolated from the human oral cavity.

Six strains of anaerobic, Gram-negative coccobacilli isolated from the root canals of patients with endodontic infections (five strains) and from a deep periodontal pocket (one strain) were subjected to a comprehensive range of phenotypic and genetic tests and were found to comprise a homogeneous group. Following 16S rRNA gene sequence analysis, they were found to be most closely related to Dialister pneumosintes, with 93 % sequence similarity between the two taxa. A novel species, Dialister invisus sp. nov., is proposed. Biochemically, the species is largely unreactive and is asaccharolytic, with only traces of acetate and propionate detected as metabolic end-products. The G+C content of the DNA of D. invisus strains is 45-46 mol%. The type strain is E7.25(T) (=CCUG 47026(T)=DSM 15470(T)).

Bacterial Proteins↗
PubMed2006

A novel RSK2 (RPS6KA3) gene mutation associated with abnormal brain MRI findings in a family with Coffin-Lowry syndrome.

Coffin-Lowry syndrome (CLS) is an X-linked mental retardation syndrome caused by defects in the RSK2 gene. We have identified a CLS family with four patients in two generations. The patients in this family, a mother and her three children (a male and two females), all have severe mental retardation with the typical CLS phenotype. In addition, brain MRI studies on the three siblings revealed abnormalities in deep subcortical white matter, thinning of the corpus callosum, hypoplastic cerebellar vermis, and asymmetry of the lateral ventricles. The degree of severity of the MRI findings correlated with the severity of mental retardation in the patients. Extensive mutation screening was performed on the entire RSK2 gene in this family. Twenty-two exons including the intron/exon junctions were amplified by PCR and subsequently sequenced on both strands. A novel mutation, a two-nucleotide insertion (298 ins TG), was identified. The insertion creates a stop codon at codon 100, resulting in a 99 amino acid truncated RSK2 protein. All patients tested have the same mutation, and no other mutation could be found in the RSK2 gene from the proband. The mutation was confirmed by PCR/RFLP. X-chromosome inactivation assay on the female patients revealed significant skewing toward inactivation of the normal RSK2 allele. Thus, this novel mutation is likely to be responsible for the unusual clinical presentation in this family, which includes full phenotypic expression in females and unique brain MRI abnormalities. The pathological function of the mutation and genotype/phenotype correlation between the mutation and this unusual clinical presentation await further clarification.

Alleles↗
PubMed1995

Co-segregation of thrombosis with the factor V Q506 mutation in an extended family with resistance to activated protein C.

The activated protein C (APC) resistance phenotype results from a mutation at one of the cleavage sites of factor V by APC (Q506). We describe a large family with an APC resistance phenotype and without any other detectable coagulation defect, including eight subjects who had developed deep venous thrombosis (mean age of the first thrombosis episode 29 years; range 17-55 years). The factor V Q506 mutation was detected in the seven patients with thrombosis who could be tested and in 13 asymptomatic subjects (mean age 17 years; range 5-33 years). The APC resistance was detectable in only 10 heterozygotes among the 19 tested. These data suggest that, in affected families, the risk for the factor V Q506 mutation carriers to develop thrombosis may be very high and that factor V genotyping must be performed in patients with thrombosis even without any detectable APC resistance phenotype.

Adult↗
PubMed2005

Plantar lipomatosis, unusual facies, and developmental delay: confirmation of Pierpont syndrome.

In 1998, Pierpont et al. reported on two unrelated boys with plantar lipomatosis, unusual facial phenotype, and developmental delay as a possible new MR/MCA syndrome. Here we report on a 2-year-old boy with similar manifestations: axial hypotonia in the first few months, prolonged feeding problems, moderate developmental delay, no speech development, deep palmar and plantar grooves, fat pads at the anteromedial aspect of the heels, and a distinct facial phenotype (high forehead, high anterior hairline, mild midfacial hypoplasia, remarkably narrow and upward slanted palpebral fissures, broad nasal ridge and tip, broad philtrum, bowed upper lip, "pouting" lower lip, full cheeks, and flat occiput). Brain MRI and MR spectroscopy studies showed relatively small frontal lobes, some widening of the lateral and third ventricles, and increased choline levels in the frontal white matter. Cytogenetic studies in lymphocytes and skin fibroblasts and whole genome micro-array CGH failed to show abnormalities. The present patient has a phenotype almost identical to that of the earlier reported children (Pierpont et al. [1998]: Am J Med Genet 75:18-21), which thereby validates this as a separate MR/MCA syndrome, appropriately designated Pierpont syndrome. The cause of the entity remains uncertain, the most likely etiologies being X-linked recessive or autosomal dominant genes.

Abnormalities, Multiple↗
PubMed2006

Three-dimensional microchannels in biodegradable polymeric films for control orientation and phenotype of vascular smooth muscle cells.

The poor mechanical strength and vasoactivity of current small-diameter tissue engineered blood vessels (TEBVs) remain unsolved problems. Given the plasticity of smooth muscle cells (SMCs), 1 of the main limitations of current scaffolding techniques is the difficulty in controlling SMC phenotype shifts in vitro. A synthetic phenotype allows the cells to rapidly proliferate and produce extracellular matrix (ECM), whereas a shift to contractile phenotype with organized ECM ultimately provides a functional blood vessel. In this study, 3D deep (65 microm) and wide microchannels separated by high-aspect ratio (8) microwalls were successfully ultraviolet (UV) microembossed using a liquid UV polymerizable biodegradable macromer (poly(epsilon-caprolactone-r-L-lactide-r-glycolide) diacrylate) and the in vitro guidance effects of varying channel width (40-160 microm) on SMCs were verified. The results show that SMCs cultured in the wider microchannels (80-160 microm wide) switch from fibroblast morphology and random orientation to spindle-shaped morphology, and align along the direction of the microchannel nearing confluence achieved with similar cell density to unpatterned film. Further, an enhanced expression of smooth muscle alpha-actin of SMCs grown on micropatterns was found nearing confluence, which demonstrates a phenotype shift to a more contractile phenotype. These films are flexible and can be folded into tubular and lamellar structures for tissue engineering of small-diameter TEBVs as well as other organs such as esophagus or intestine. These results suggest that these micropatterned synthetic biodegradable scaffolds may be useful for guiding SMCs to grow into functional, small-diameter vascular grafts.

Animals↗
PubMed2002

Involvement of surface polysaccharides in the organic acid resistance of Shiga Toxin-producing Escherichia coli O157:H7.

In general, wild Escherichia coli strains can grow effectively under moderately acidic organic acid-rich conditions. We found that the Shiga Toxin-producing E. coli (STEC) O157:H7 NGY9 grows more quickly than a K-12 strain in Luria-Bertani (LB)-2-morpholinoethanesulphonic acid (MES) broth supplemented with acetic acid (pH 5.4). Hypothesizing that the resistance of STEC O157:H7 to acetic acid is as a result of a mechanism(s) other than those known, we screened for STEC mutants sensitive to acetic acid. NGY9 was subjected to mini-Tn5 mutagenesis and, from 50,000 colonies, five mutants that showed a clear acetic acid-sensitive phenotype were isolated. The insertion of mini-Tn5 in three mutants occurred at the fcl, wecA (rfe) and wecB (rffE) genes and caused loss of surface O-polysaccharide, loss of both O-polysaccharide and enterobacterial common antigen (ECA) and loss of ECA respectively. The other two mutants showed inactivation of the waaG (rfaG) gene but at different positions that caused a deep rough mutant with loss of the outer core oligosaccharide of lipopolysaccharide (LPS) as well as phenotypic loss of O-polysaccharide and ECA. With the introduction of plasmids carrying the fcl, wecA, wecB and waaG genes, respectively, all mutants were complemented in their production of O-polysaccharide and ECA, and normal growth was restored in organic acid-rich culture conditions. We also found that the growth of Salmonella LPS mutants Ra, Rb1, Rc, Rd1, Rd2 and Re was suppressed in the presence of acetic acid compared with that of the parents. These results suggest that the full expression of LPS (including O-polysaccharide) and ECA is indispensable to the resistance against acetic acid and other short chain fatty acids in STEC O157:H7 and Salmonella. To the best of our knowledge, this is a newly identified physiological role for O-polysaccharide and ECA as well as an acid resistance mechanism.

Acetic Acid↗
PubMed2000

Rapid characterisation of deep-sea actinomycetes for biotechnology screening programmes.

A continual need in natural product discovery is dereplication, that is the ability to exclude previously tested microorganisms from screening programmes. Whole-cell fingerprinting techniques offer an ideal solution to this problem because of their rapidity and reproducibility, dependence on small samples, and automation. One such technique, Curie-point pyrolysis mass spectrometry (PyMS), has been deployed for the characterisation of a unique collection of actinomycetes recovered from Pacific Ocean sediments approximately 2000 to 6500 m below sea level. This paper addresses the question: to what extent are pyrogroups, defined on the basis of PyMS fingerprinting, related to classifications derived from more conventional microbial systematics? A collection of 44 randomly chosen deep-sea rhodococci were coded and subjected to a double-blind PyMS and numerical taxonomic (NT) analysis; the latter sorted the strains into clusters (taxospecies) using large sets of equally weighted phenotypic data. At the end of the experiment the codes were disclosed and the NT classification shown to generate 6 homogeneous clusters corresponding to different deep-sea sites. The matching of these clusters with the resulting pyrogroups was very high with an overall congruence of nearly 98%. Thus, PyMS characterisation is directly ascribable to the phenotypic variation being sought for biotechnology screens. Moreover, the exquisite discriminatory power of PyMS readily revealed infraspecific diversity in these industrially important bacteria.

Actinomycetales↗