Generation Of Phylogenetic Trees Research Articles

Genetic relatedness among Neisseria gonorrhoeae isolates in southeastern Michigan

Background: Antimicrobial resistance (AMR) in Neisseria gonorrhoeae (NG) is an emerging public health crisis. Whole-genome sequencing (WGS) is an efficient way of predicting AMR determinants and their spread in the population. In a previous study, genotype–phenotype correlation analyses among NG isolates to determine antimicrobial resistance revealed discordance for azithromycin (AZM) and ceftriaxone (CRO) compared to other antibiotics. We investigated the evolutionary relatedness of NG isolated from patients with sexually transmitted infection (STI) using WGS in southeastern Michigan. Methods: Isolates, corresponding demographic data, and minimum inhibitory concentrations (MIC) via E-test (CRO) and broth microdilution (AZM) were obtained from the Michigan Department of Health and Human Services. Whole-genome libraries were prepared using the QIAseq FX kit followed by sequencing on a NovaSeq6000 (>200X Coverage); samples were aligned to NG reference strain TUM19854 (NZ_AP023069.1) using Snippy before phylogenetic tree generation using Neighbor-joining clustering on the core.aln files. Phylogenetic trees were visualized using ATGC:PRESTO. Results: In total, 38 isolates were analyzed. Demographic data and susceptibility testing results are noted in Table 1. Most isolates were from males (63%), Blacks (44.7%), individuals living in Detroit City proper (47.3%), and those with unknown HIV status (55.2%). More than one-third had prior STI, including NG. All isolates were susceptible to CRO (CLSI susceptible breakpoint MIC, 1). Within the phylogenetic tree, 8 main branches were identified (Fig. 1). Moreover, 1 branch contained a cluster with 12 closely related isolates, which included the 9 isolates with nonsusceptible AZM. Nearly all isolates in that cluster had been collected from Detroit City proper and Wayne County, suggesting epidemiological overlap and potential spread of resistant strains in those counties.Conclusions: Comparative whole-genome and phylogenetic analyses among a subset of NG isolates revealed clustering of AZM resistance strains, suggesting a genomic component to AMR. Further studies are needed to determine the utility of WGS in diagnosis, outbreak investigations, and management of NG infections.Disclosures: None

Recognition of Timestamps and Reconstruction of the Line of Organism Development

In this work, an artificial neural network is used to recognize timestamps of evolution. Timestamps are associated with outliers determined during the recognition of the genome attractors of organisms. The aim of this work is to present a new method of penetrating deep into evolution using the recognized timestamps. To achieve this aim, the neural networks of different number of layers were implemented in order to check the influence of the number of layers on the visibility of the timestamps. Moreover, the teaching process was repeated 10 times for each implemented neural network. The recognition of each organism evolution was also repeated 10 times for each taught neural network to increase the reliability of the results. It is presented, among other findings, that during the recognition of the timestamps of evolution not only the number of homologous comparisons and the lengths of compared sequences are important but also the distribution of similarities between sequences. It is also presented that the recognized timestamps allow for travel between genome attractors and reconstruct the line of organism development from the most advanced to the most primitive organisms. The results were validated by determining timestamps for exemplary sets of organisms and also in relation to semihomology approach and by phylogenetic tree generation.

E3 ubiquitin ligase PbrATL18 is a positive factor in pear resistance to drought and Colletotrichum fructicola infection

The Arabidopsis Tóxicos en Levadura (ATL) protein is a subfamily of the E3 ubiquitin ligases, which exists widely in plants and is extensively involved in plant growth and development. Although the ATL family has been identified in other species, such as Arabidopsis, Oryza sativa, and grapevine, few reports on pear ATL gene families have been reported. In this study, 92 PbrATL genes were identified and analyzed from the Pyrus breschneideri genome. Motif analysis and phylogenetic tree generation divided them into nine subgroups, and chromosome localization analysis showed that the 92 PbrATL genes were distributed in 16 of 17 pear chromosomes. Transcriptome data and quantitative real-time polymerase chain reaction (qRT-PCR) experiments demonstrated that PbrATL18, PbrATL41, and PbrATL88 were involved in both pear drought resistance and Colletotrichum fructicola infection. In addition, Arabidopsis thaliana overexpressing PbrATL18 showed greater resistance to drought stress than the wild type (WT), and PbrATL18-silenced pear seedlings showed greater sensitivity to drought and C. fructicola infection than the controls. PbrATL18 regulated plant resistance by regulating chitinase (CHI), phenylalanine ammonia-lyase (PAL), polyphenol oxidase (PPO), catalase (CAT), peroxidase (POD), and superoxide dismutase (SOD) activities. This study provided a reference for further exploring the functions of the PbrATL gene in drought resistance and C. fructicola infection.

PTGAC Model: A machine learning approach for constructing phylogenetic tree to compare protein sequences.

This work proposes a machine learning-based phylogenetic tree generation model based on agglomerative clustering (PTGAC) that compares protein sequences considering all known chemical properties of amino acids. The proposed model can serve as a suitable alternative to the Unweighted Pair Group Method with Arithmetic Mean (UPGMA), which is inherently time-consuming in nature. Initially, principal component analysis (PCA) is used in the proposed scheme to reduce the dimensions of 20 amino acids using seven known chemical characteristics, yielding 20 TP (Total Points) values for each amino acid. The approach of cumulative summing is then used to give a non-degenerate numeric representation of the sequences based on these 20 TP values. A special kind of three-component vector is proposed as a descriptor, which consists of a new type of non-central moment of orders one, two, and three. Subsequently, the proposed model uses Euclidean Distance measures among the descriptors to create a distance matrix. Finally, a phylogenetic tree is constructed using hierarchical agglomerative clustering based on the distance matrix. The results are compared with the UPGMA and other existing methods in terms of the quality and time of constructing the phylogenetic tree. Both qualitative and quantitative analysis are performed as key assessment criteria for analyzing the performance of the proposed model. The qualitative analysis of the phylogenetic tree is performed by considering rationalized perception, while the quantitative analysis is performed based on symmetric distance (SD). On both criteria, the results obtained by the proposed model are more satisfactory than those produced earlier on the same species by other methods. Notably, this method is found to be efficient in terms of both time and space requirements and is capable of dealing with protein sequences of varying lengths.

FishPhyloMaker: An R package to generate phylogenies for ray-finned fishes

Phylogenies summarize evolutionary information that is essential in the investigation of ecological and evolutionary causes of diversity patterns. They allow investigating hypotheses from trait evolution to the relationship between evolutionary diversity and ecosystem functioning. However, obtaining a comprehensive phylogenetic hypothesis can be difficult for some groups, especially those with a high number of species, that is the case for fishes, particularly tropical ones. The lack of species in phylogenetic hypotheses, called Darwinian shortfalls, can hinder ecological and evolutionary studies involving this group. To tackle this problem, we developed FishPhyloMaker, an R package that facilitates the generation of phylogenetic trees through a reliable and reproducible procedure, even for a large number of species. The package adopts well-known rules of insertion based on cladistic hierarchy, allowing its use by specialists and non-specialists in fish systematics. We tested the reliability of our algorithm in maintaining important properties of phylogenetic distances running a sensitivity analysis. We also exemplified the use of the FishPhyloMaker package by constructing complete phylogenies for fishes inhabiting the four richest freshwater ecoregions of the world. Furthermore, we proposed a new method to calculate Darwinian shortfalls and mapped this information for the major freshwater drainages of the world. FishPhyloMaker will expand the range of evolutionary and ecological questions that can be addressed using ray-finned fishes as study models, mainly in the field of community phylogenetics, by providing an easy and reliable way to obtain comprehensive phylogenies. Further, FishPhyloMaker presents the potential to be extended to other taxonomic groups that suffer from the same difficulty in the obtention of comprehensive phylogenetic hypothesis.

Diversity of Endophtic Bacteria in Aerides crispa, an Epiphytic Orchid

Aerides crispa is an epiphytic flowering orchid belongs to the family Orchidaceae.we have identified five different endophytic bacteria from this orchid. Genotypic characterization of the bacterial culture was done using 16S rDNA sequencing after PCR amplification. These sequences were compared with the known similar bacterial sequences from the NCBI GenBank database. Homological relationship of the bacteria was also compared by Phylogenetic tree generation. Bacteria obtained were Bacillus pumilus MT463728, Bacillus megaterium MT540506, Lysinibacillus fusiformis MT540507, Bacillus cereus MT540510, Aneurinibacillus migulanus. From the study, we have molecularly characterized and documented five different endophytic bacteria from the epiphytic orchid, A crispa. This shows the diversity of endophytes in orchids which speaks a lot about the urgent necessity of bioconservation without words.

Variant analysis of SARS-CoV-2 genomes in the Middle East

BackgroundCoronavirus (COVID-19) was introduced into society in late 2019 and has now reached over 88 million cases and 1.9 million deaths. The Middle East has a death toll of ~80,000 and over 35000 of these are in Iran, which has over 1.2 million confirmed cases. We expect that Iranian cases caused outbreaks in the neighbouring countries and that variant mapping and phylogenetic analysis can be used to prove this. We also aim to analyse the variants of severe acute respiratory syndrome coronavirus-2 (SARS -CoV-2) to characterise the common genome variants and provide useful data in the global effort to prevent further spread of COVID-19. MethodsThe approach uses bioinformatics approaches including multiple sequence alignment, variant calling and annotation and phylogenetic analysis to identify the genomic variants found in the region. The approach uses 122 samples from the 13 countries of the Middle East sourced from the Global Initiative on Sharing All Influenza Data (GISAID). FindingsWe identified 2200 distinct genome variants including 129 downstream gene variants, 298 frame shift variants, 789 missense variants, 1 start lost, 13 start gained, 1 stop lost, 249 synonymous variants and 720 upstream gene variants. The most common, high impact variants were 10818delTinsG, 2772delCinsC, 14159delCinsC and 2789delAinsA. These high impact variant ultimately results in 36 number of mutations on spike glycoprotein. Variant alignment and phylogenetic tree generation indicates that samples from Iran likely introduced COVID-19 to the rest of the Middle East. InterpretationThe phylogenetic and variant analysis provides unique insight into mutation types in genomes. Initial introduction of COVID-19 was most likely due to Iranian transmission. Some countries show evidence of novel mutations and unique strains. Increased time in small populations is likely to contribute to more unique genomes. This study provides more in depth analysis of the variants affecting in the region than any other study.

Genome-scale reconstructions to assess metabolic phylogeny and organism clustering.

Approaches for systematizing information of relatedness between organisms is important in biology. Phylogenetic analyses based on sets of highly conserved genes are currently the basis for the Tree of Life. Genome-scale metabolic reconstructions contain high-quality information regarding the metabolic capability of an organism and are typically restricted to metabolically active enzyme-encoding genes. While there are many tools available to generate draft reconstructions, expert-level knowledge is still required to generate and manually curate high-quality genome-scale metabolic models and to fill gaps in their reaction networks. Here, we use the tool AutoKEGGRec to construct 975 genome-scale metabolic draft reconstructions encoded in the KEGG database without further curation. The organisms are selected across all three domains, and their metabolic networks serve as basis for generating phylogenetic trees. We find that using all reactions encoded, these metabolism-based comparisons give rise to a phylogenetic tree with close similarity to the Tree of Life. While this tree is quite robust to reasonable levels of noise in the metabolic reaction content of an organism, we find a significant heterogeneity in how much noise an organism may tolerate before it is incorrectly placed in the tree. Furthermore, by using the protein sequences for particular metabolic functions and pathway sets, such as central carbon-, nitrogen-, and sulfur-metabolism, as basis for the organism comparisons, we generate highly specific phylogenetic trees. We believe the generation of phylogenetic trees based on metabolic reaction content, in particular when focused on specific functions and pathways, could aid the identification of functionally important metabolic enzymes and be of value for genome-scale metabolic modellers and enzyme-engineers.

Evolution of endonuclease IV protein family: an in silico analysis.

DNA repair is one of the key cellular events which balances between evolvability and integrity of thegenome. Endonuclease IV enzymes are class II AP endonucleases under base excision repair pathway which act on abasic site and break the phosphodiester bond at the 5' side. The role and activity of endonuclease IV proteins vary among different organisms; even it is absent in higher eukaryotes. The evolution of this protein family was studied by analyzing all homologs of the endonuclease IV protein family through different in silico techniques including phylogenetic tree generation and model building. The sequence analysis revealed four consensus sequence motifs within the AP2EC domain which are functionally important and conserved throughout the evolution process. It was also observed that the species and endonuclease IV gene evolution shape up differently in most of the organisms. Presence of the mitochondria-targeted signal peptides in fungal species Saccharomyces and Coccidioides suggest a possible endosymbiotic transfer of endonuclease IV genes to lower eukaryotes. Evolutionary changes among various clades in the protein-based phylogenetic tree have been investigated by comparison of homology models which suggests the conservation of overall fold of endonuclease IV proteins except for few alterations in loop orientation in few clades.

Single-cell genetic analysis of clonal dynamics in colorectal adenomas indicates CDX2 gain as a predictor of recurrence.

Colorectal adenomas are common precancerous lesions with the potential for malignant transformation to colorectal adenocarcinoma. Endoscopic polypectomy provides an opportunity for cancer prevention; however, recurrence rates are high. We collected formalin-fixed paraffin-embedded tissue of 15 primary adenomas with recurrence, 15 adenomas without recurrence, and 14 matched pair samples (primary adenoma and the corresponding recurrent adenoma). The samples were analysed by array-comparative genomic hybridisation (aCGH) and single-cell multiplex interphase fluorescence in situ hybridisation (miFISH) to understand clonal evolution, to examine the dynamics of copy number alterations (CNAs) and to identify molecular markers for recurrence prediction. The miFISH probe panel consisted of 14 colorectal carcinogenesis-relevant genes (COX2, PIK3CA, APC, CLIC1, EGFR, MYC, CCND1, CDX2, CDH1, TP53, HER2, SMAD7, SMAD4 and ZNF217), and a centromere probe (CEP10). The aCGH analysis confirmed the genetic landscape typical for colorectal tumorigenesis, that is, CNAs of chromosomes 7, 13q, 18 and 20q. Focal aberrations (≤10 Mbp) were mapped to chromosome bands 6p22.1-p21.33 (33.3%), 7q22.1 (31.4%) and 16q21 (29.4%). MiFISH detected gains of EGFR (23.6%), CDX2 (21.8%) and ZNF217 (18.2%). Most adenomas exhibited a major clone population which was accompanied by multiple smaller clone populations. Gains of CDX2 were exclusively seen in primary adenomas with recurrence (25%) compared to primary adenomas without recurrence (0%). Generation of phylogenetic trees for matched pair samples revealed four distinct patterns of clonal dynamics. In conclusion, adenoma development and recurrence are complex genetic processes driven by multiple CNAs whose evaluations by miFISH, with emphasis on CDX2, might serve as a predictor of recurrence.

BIIGA: Bioinformatics inspired image grouping approach

Initial work on image phylogeny used different approaches like the minimum spanning tree etc. The less investigated attempt is a bioinformatics-inspired approach for image phylogeny. The aim of this paper is to bridge this gap by generating image phylogeny with the concept of phylogenetic trees in bioinformatics. These trees were developed by using multiple aligned DNA sequences of original or multiple print-scan (MPS) degraded variants of watermarked (W) and non-watermarked (NW) images. Experimental results disclosed the viability of a proposed novel approach and effectively grouped original or MPS degraded variants of the W or NW images. The proposed method’s claims may revolutionise our knowledge of degraded (D) or non-degraded (ND) W and NW image grouping. It may direct to a new era of phylogenetic tree-based W or NW degraded or original images for developing the next generation of degraded (by MPS) W and NW grouping softwares. To the best of our knowledge, this is the first time such a method has been employed for image grouping. Our contributions are: (a) biologically-based image encoding to DNA letters (b) multiple sequence alignment (MSA) of DNA-encoded images (c) phylogenetic tree generation to group MPS-degraded W or NW images.

Algorithms for reconstruction of chromosomal structures

BackgroundOne of the main aims of phylogenomics is the reconstruction of objects defined in the leaves along the whole phylogenetic tree to minimize the specified functional, which may also include the phylogenetic tree generation. Such objects can include nucleotide and amino acid sequences, chromosomal structures, etc. The structures can have any set of linear and circular chromosomes, variable gene composition and include any number of paralogs, as well as any weights of individual evolutionary operations to transform a chromosome structure. Many heuristic algorithms were proposed for this purpose, but there are just a few exact algorithms with low (linear, cubic or similar) polynomial computational complexity among them to our knowledge. The algorithms naturally start from the calculation of both the distance between two structures and the shortest sequence of operations transforming one structure into another. Such calculation per se is an NP-hard problem.ResultsA general model of chromosomal structure rearrangements is considered. Exact algorithms with almost linear or cubic polynomial complexities have been developed to solve the problems for the case of any chromosomal structure but with certain limitations on operation weights. The computer programs are tested on biological data for the problem of mitochondrial or plastid chromosomal structure reconstruction. To our knowledge, no computer programs are available for this model.ConclusionsExactness of the proposed algorithms and such low polynomial complexities were proved. The reconstructed evolutionary trees of mitochondrial and plastid chromosomal structures as well as the ancestral states of the structures appear to be reasonable.Electronic supplementary materialThe online version of this article (doi:10.1186/s12859-016-0878-z) contains supplementary material, which is available to authorized users.

MamA as a Model Protein for Structure-Based Insight into the Evolutionary Origins of Magnetotactic Bacteria.

MamA is a highly conserved protein found in magnetotactic bacteria (MTB), a diverse group of prokaryotes capable of navigating according to magnetic fields – an ability known as magnetotaxis. Questions surround the acquisition of this magnetic navigation ability; namely, whether it arose through horizontal or vertical gene transfer. Though its exact function is unknown, MamA surrounds the magnetosome, the magnetic organelle embedding a biomineralised nanoparticle and responsible for magnetotaxis. Several structures for MamA from a variety of species have been determined and show a high degree of structural similarity. By determining the structure of MamA from Desulfovibrio magneticus RS-1 using X-ray crystallography, we have opened up the structure-sequence landscape. As such, this allows us to perform structural- and phylogenetic-based analyses using a variety of previously determined MamA from a diverse range of MTB species across various phylogenetic groups. We found that MamA has remained remarkably constant throughout evolution with minimal change between different taxa despite sequence variations. These findings, coupled with the generation of phylogenetic trees using both amino acid sequences and 16S rRNA, indicate that magnetotaxis likely did not spread via horizontal gene transfer and instead has a significantly earlier, primordial origin.

Structure and sequence based analysis of alpha-amylase evolution.

α-Amylases hydrolyze α- 1,4-glycosidic bonds during assimilation of biological macromolecules. The amino acid sequences of these enzymes in thousands of diverse organisms are known and the 3D structures of several proteins have been solved. The 3D structure analysis of these universal enzymes from diverse organisms has been studied by the generation of phylogenetic trees and structure based sequence analysis to generate a metric for the degree of conservation that is responsible for individual speciation. Greater similarities are observed between reference NCBI tree and structure based phylogenetic tree compared to sequence based phylogenetic tree indicating that structures truly represent the functional aspects of proteins than from the sequence information alone. We report differences in the profile specific conserved and insertion/deletion regions, factors responsible for the Ca(2+) and Cl(-) ion binding and the disulfide connectivity pattern that discriminate the enzymes over evolution.

The RAS subfamily Evolution - tracing evolution for its utmost exploitation.

In the development of multicellularity, signaling proteins has played a very important role. Among them, RAS family is one of the most widely studied protein family. However, evolutionary analysis has been carried out mainly on super family level leaving sub family information in scanty. Thus, a subfamily evolutionary study on RAS evolutionary expansion is imperative as it will aid in better drug designing against dreadful diseases like Cancer and other developmental diseases. The present study was aimed to understand RAS evolution on both holistic as well as reductive level. All human RAS family genes and protein were subjected to BLAST tools to find orthologs and paralogs with different parameters followed by phylogenetic tree generation. Our results clearly showed that H-RAS is the most primitive RAS in higher eukaryotes and then diverged into other RAS family members due to different gene modification events. Furthermore, a site specific selection pressure analysis was carried out using SELECTON server which showed that H-RAS, M-RAS and N-RAS are evolving faster than K-RAS and R-RAS. Thus, the results ascertain a new ground to cancer biologists to exploit negatively selected K-RAS and R-RAS as potent drug targets in cancer therapeutics.

Characterization of major histocompatibility complex DRA and DRB genes of the forest musk deer (Moschus berezovskii)

The forest musk deer (Moschus berezovskii) is one of the most endangered species in China. Over the past decades, extensive hunting and poaching have pushed the forest musk deer to the edge of extinction, and conservation biologists are presently pursuing scientific management plans to rescue this species. The major histocompatibility complex (MHC), a cluster of genes responsible for antigen presentation, is a highly polymorphic genomic region in vertebrates that has become a popular functional marker system for studying adaptive variation. In this study, we developed locus-specific genotyping primers for exon 2 fragments of one DRA gene and one DRB locus of the forest musk deer using a suite of comprehensive methods that included universal primer amplification, genome walking, single-strand conformation polymorphism (SSCP), heteroduplex (HD) profiling, and sequence analysis. Each forest musk deer showed no more than two sequences per locus, confirming the specificity of our primers. Genotyping with these primers allowed us to identify two DRA alleles and six DRB alleles in a captive breeding population of the Sichuan Musk Deer Breeding Institution. For the DRA locus, we found a slightly higher observed heterozygosity (NO=0.154) than expected (NE=0.143). In contrast, the DRB locus showed a significant heterozygote deficiency (NO=0.508; NE=0.761; P<0.05), which was probably due to inbreeding in the captive population. An obvious excess of nonsynonymous substitutions over synonymous was observed at the antigen-binding positions of the DRA and DRB loci, showing the presence of positive selection in the forest musk deer DR genes. Finally, generation of phylogenetic trees for the DRA and DRB sequences of the forest musk deer and other ruminants revealed that the DRA and DRB loci identified in this study had homologous relationships with the known ruminant DRA and DRB genes. Based on this analysis, and to facilitate future studies, we named these novel loci Mobe-DRA and Mobe-DRB3.

Diversity of Fimbrillin among &lt;i&gt;Porphyromonas gulae&lt;/i&gt; Clinical Isolates from Japanese Dogs

Porphyromonas gulae, a gram-negative black-pigmented anaerobe, is a pathogen for periodontitis in dogs. An approximately 41-kDa fimbrial subunit protein (FimA) encoded by fimA is regarded as associated with periodontitis. In the present study, the fimA genes of 17 P. gulae strains were sequenced, and classified into two major types. The generation of phylogenetic trees based on the deduced amino acid sequence of FimA of P. gulae strains along with sequences from several strains of Porphyromonas gingivalis, a major cause of human periodontitis, revealed that the two types of FimA (types A and B) of P. gulae were similar to type I FimA and types II and III FimA of P. gingivalis, respectively. A PCR system for classification was established based on differences in the nucleotide sequences of the fimA genes. Analysis of 115 P. gulae-positive oral swab specimens from dogs revealed that 42.6%, 22.6%, and 26.1% of them contained type A, type B, and both type A and B fimA genes, respectively. Experiments with a mouse abscess model demonstrated that the strains with type B fimA caused significantly greater systemic inflammation than those with type A. These results suggest that the FimA proteins of P. gulae are diverse with two major types and that strains with type B fimA could be more virulent.

Comparison of Barley Stripe Mosaic Virus Strains

BSMV (barley stripe mosaic virus) particles were obtained in a pure state from infected host plant tissues of Hordeum vulgare. The three genomic parities (alpha, beta and gamma) were amplified by PCR using specific primers for each particle; each was cloned. Partial sequence of the alpha, beta and gamma segments was determined for the Egyptian isolate of barley stripe mosaic virus (BSMV AE1). Alignment of nucleotide sequences with that of other known strains of the virus, BSMV type strains (CV17, ND18 and China), and the generation of phylogenetic trees was performed. A low level of homology was detected comparing 467 bp of the a and 643 bp of the segments to that of the other strains, and thus BSMV alpha and beta segments were in separate clusters. However, 1154 bp of the gamma segments of BSMV AE1 showed a high level of homology especially to strain BSMV ND18, as they both formed a distinct cluster. Northern blotting of pure BSMV AE1 virus and H. vulgare-infected tissue were compared using an alpha ND18 specific probe. Western blotting using antibodies specific for the coat protein (CP) and the triple gene block 1 (TGB1) protein, which are both encoded by the beta ND18 segment, still indicated a high level of similarity between proteins produced by BSMV ND18 and AE1. We suggest that the BSMV AE1 isolate is a distinct strain of BSMV which reflects the genetic evolutionary divergence among BSMV strains and members of the Hordeivirus group.

Streptomyces durmitorensis sp. nov., a producer of an FK506-like immunosuppressant

Screening of soil samples from the Durmitor National Park, Serbia and Montenegro, for strains producing immunosuppressants with a similar mechanism of action to FK506 resulted in the isolation of the actinomycete strain MS405(T). Isolate MS405(T) was found to have morphological and phenotypic properties that were consistent with its classification as a Streptomyces strain. The DNA G+C content of strain MS405(T) was 72 mol%. 16S rRNA gene sequence data confirmed the taxonomic position of the strain, following the generation of phylogenetic trees by using various treeing algorithms. On the basis of 16S rRNA gene sequence similarity, strain MS405(T) was shown to belong to the Streptomyces albidoflavus 'supercluster', being related to Streptomyces aureus DSM 41785(T) (99.59 % similarity) and Streptomyces kanamyceticus DSM 40500(T) (99.32 %). The 16S-23S rRNA internally transcribed spacer (ITS) region exhibited variations in length and sequence composition, showing limited usefulness in phylogenetic analyses. However, DNA relatedness values support the classification of this isolate within a novel species. A number of physiological and biochemical tests distinguished strain MS405(T) from its closest phylogenetic neighbours. Therefore, strain MS405(T) represents a novel species, for which the name Streptomyces durmitorensis sp. nov. is proposed, with the type strain MS405(T) (=DSM 41863(T) =CIP 108995(T)).

Five novel Kitasatospora species from soil: Kitasatospora arboriphila sp. nov., K. gansuensis sp. nov., K. nipponensis sp. nov., K. paranensis sp. nov. and K. terrestris sp. nov.

A polyphasic study was carried out to establish the taxonomic positions of six strains isolated from diverse soil samples and provisionally assigned to the genus Kitasatospora. The isolates were found to have chemical and morphological properties consistent with their classification as Kitasatospora strains. Direct 16S rRNA gene sequence data confirmed the taxonomic position of the strains following the generation of phylogenetic trees by using three tree-making algorithms. Five of the isolates were considered to merit species status using complementary genotypic and phenotypic data. These organisms were designated Kitasatospora arboriphila sp. nov. (HKI 0189(T)=2291-120(T)=DSM 44785(T)=NCIMB 13973(T)), Kitasatospora gansuensis sp. nov. (HKI 0314(T)=2050-015(T)=DSM 44786(T)=NCIMB 13974(T)), Kitasatospora nipponensis sp. nov. (HKI 0315(T)=2148-013(T)=DSM 44787(T)=NCIMB 13975(T)), Kitasatospora paranensis sp. nov. (HKI 0190(T)=2292-041(T)=DSM 44788(T)=NCIMB 13976(T)) and Kitasatospora terrestris sp. nov. (HKI 0186(T)=2293-012(T)=DSM 44789(T)=NCIMB 13977(T)). The remaining organism, isolate HKI 0316 (=2122-022=DSM 44790=NCIMB 13978), was considered to be a strain of Kitasatospora kifunensis on the basis of 16S rRNA gene sequence, DNA-DNA relatedness and phenotypic data.