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Phylogenetic analysis based on 16S rRNA gene sequences of the genus Streptomyces showed the presence of six distinguishable clusters, with 100 % sequence similarity values among strains in each cluster; thus they shared almost the same evolutionary distance. This result corroborated well with the outcome of core gene (orthologous gene clusters) based genome phylogeny analysis of 190 genomes including the Streptomyces species in those six clusters. These preeminent results led to an investigation of genome-based indices such as digital DNA–DNA hybridization (dDDH), average nucleotide identity (ANI) and average amino acid identity (AAI) for the strains in those six clusters. Certain strains recorded genomic indices well above the threshold values (70 %, 95–96 % and >95 % for dDDH, ANI and AAI, respectively) determined for species affiliation, suggesting only one type strain belongs to described species and the other(s) may need to be reduced in taxa to a later heterotypic synonym. To conclude, the results of comprehensive analyses based on phylogenetic and genomic indices suggest that the following six reclassifications are proposed: Streptomyces flavovariabilis as a later heterotypic synonym of Streptomyces variegatus ; Streptomyces griseofuscus as a later heterotypic synonym of Streptomyces murinus ; Streptomyces kasugaensis as a later heterotypic synonym of Streptomyces celluloflavus ; Streptomyces luridiscabiei as a later heterotypic synonym of Streptomyces fulvissimus ; Streptomyces pharetrae as a later heterotypic synonym of Streptomyces glaucescens ; and Streptomyces stelliscabiei as a later heterotypic synonym of Streptomyces bottropensis .

Streptomyces, one of the largest genera belonging to the phylum Actinobacteria, contribute to more than 60% of the clinically relevant antibiotics. The present study outlined the genomics and the metabolomics of a mangrove-derived Streptomyces murinus THV12 strain. The Illumina Hiseq 2500 platform-based whole-genome sequencing of the Streptomyces strain generated a consensus sequence of 8,363,247 bp with 107 contigs and 7345 protein-coding genes, which shared significant homology with genes from Streptomyces murinus. The detection of secondary metabolite biosynthetic gene clusters (smBGCs) in the genome performed using the pipeline antiSMASH v6.1.1 revealed that the strain harbored 47 secondary metabolite clusters, which represented 17.9% of the 8.3 Mb genome. The smBGCs belonged to the metabolite categories: PKS, NRPS, ectoine, lassopeptides, lantipeptides, melanin, siderophores, terpenes and other putative products. The strain showed broad-spectrum antimicrobial activity with a inhibition zone of 30 mm against Gram-positive bacteria and Candida albicans. The secondary metabolite profiling of the crude extracts from the fermentation broth of THV12 was performed with the HPLC system coupled with an Orbitrap Exploris120 high-resolution mass spectrometer. As revealed by in silico analysis, compounds such as actinomycin D, pentamycin, desferrioxamine E and cinnabaramide A were detected with MS/MS analysis. Apart from this, compounds belonging to different chemical scaffolds, such as cyclic and linear peptides, bacterial alkaloids, linear polyketides and terpenoids, were also present in the fermentation broth of the strain when cultivated under the OSMAC (One Strain Many Compounds) approach. Thus, the combined strategy of genome mining and metabolomics of the mangrove-derived strain aided in exploring the chemical diversity of BGCs and new chemical entities, which can contribute to drug leads.

This study aimed to clarify the taxonomic relationships among Streptomyces costaricanus , Streptomyces graminearus, Streptomyces murinus and Streptomyces phaeogriseichromatogenes . These strains share the same 16S rRNA gene sequence. Multilocus sequence analysis revealed that S. costaricanus , S. murinus and S. phaeogriseichromatogenes belong to the same species, but S. graminearus does not. Digital DNA–DNA relatedness and average nucleotide identity among S. costaricanus, S. murinus and S. phaeogriseichromatogenes were 70.9–74.6% and 96.5–97.0 %, respectively. In addition to the previously reported phenotypic data, the presence of a similar set of secondary metabolite-biosynthetic gene clusters for polyketides and nonribosomal peptides supported the similarity among the three species. Therefore, S. costaricanus and S. phaeogriseichromatogenes should be reclassified as later heterotypic synonyms of S. murinus .

Damping-off caused by Pythium aphanidermatum (Pa) is one of the most destructive diseases for watemelon seedlings. Application of biological control agents against Pa has attracted attention of many researchers for a long time. In this study, an actinomycete isolate JKTJ-3 with strong and broad-spectrum antifungal effect was screened from 23 bacterial isolates. Based on the morphological, cultural, physiological, and biochemical characteristics as well as the feature of 16S rDNA sequence, isolate JKTJ-3 was identified as Streptomyces murinus. We compared the biocontrol efficacy of isolate JKTJ-3 and its metabolites. The results revealed that seed and substrate treatments with the JKTJ-3 cultures showed a significant inhibitory effect on watermelon damping-off disease. Seed treatment with the JKTJ-3 cultural filtrates (CF) had higher control efficacy that of the fermentation cultures (FC). Treatment of the seeding substrate with the wheat grain cultures (WGC) of JKTJ-3 exhibited better control efficacy than that of the seeding substrate with the JKTJ-3 CF. Moreover, the JKTJ-3 WGC showed the preventive effect on suppression of the disease, and the efficacy increased with increase in the inoculation interval between the WGC and Pa. Production of the antifungal metabolite actinomycin D by isolate JKTJ-3 and cell wall-degrading enzymmes such as β-1,3-glucanase and chitosanase was probably the mechanisms for effective control of watermelon damping-off. It was showed for the first time that S. murinus can produce anti-oomycete substances including chitinase and actinomycin D. This is the first report about S. murinus used as biocontrol agent against watermelon Pa-induced damping-off.

The structure of cell wall teichoic acids was studied by chemical methods and NMR spectroscopy in the type strains of two actinomycete species of the “Streptomyces griseoviridis” phenetic cluster: streptomyces daghestanicus and streptomyces murinus. S. daghestanicus VKM Ac-1722t contained two polymers having a 1,5-poly(ribitol phosphate) structure. In one of them, the ribitol units had α-rhamnopyranose and 3-O-methyl-α-rhamnopyranose substituents; in the other, each ribitol unit was carrying 2,4-ketal-bound pyruvic acid. Such polymers were earlier found in the cell walls of Streptomyces roseolus and Nocardiopsis albus, respectively; however, their simultaneous presence in the cell wall has never been reported. The cell wall teichoic acid of Streptomyces murinus INA-00524T was a 1,5-poly(glucosylpolyol phosphate), whose repeating unit was [-6)-β-D-glucopyranosyl-(1→2)-glycerol phosphate-(3-P-]. Such a teichoic acid was earlier found in Spirilliplanes yamanashiensis. The 13C NMR spectrum of this polymer is presented for the first time. The results of the present investigation, together with earlier published data, show that the type strains of four species of the “Streptomyces griseoviridis” phenetic cluster differ in the composition and structure of their teichoic acids; thus, teichoic acids may serve as chemotaxonomic markers of the species.

The structure of cell wall teichoic acids was studied by chemical methods and NMR spectroscopy in the type strains of two actinomycete species of the "Streptomyces griseoviridis" phenetic cluster: Streptomyces daghestanicus and Streptomyces murinus. S. daghestanicus VKM Ac-1722T contained two polymers having a 1,5-poly(ribitol phosphate) structure. In one of them, the ribitol units had alpha-rhamnopyranose and 3-O-methyl-alpha-rhamnopyranose substituents; in the other, each ribitol unit was carrying 2,4-ketal-bound pyruvic acid. Such polymers were earlier found in the cell walls of Streptomyces roseolus and Nocardiopsis albus, respectively; however, their simultaneous presence in the cell wall has never been reported. The cell wall teichoic acid of Streptomyces murinus INA-00524T was is a 1,5-poly(glucosylpolyol phosphate), whose repeating unit was [-6)-beta-D-glucopyranosyl-(1 --2)-glycerol phosphate-(3-P-]. Such a teichoic acid was earlier found in Spirilliplanes yamanashiensis. The 13C NMR spectrum of this polymer is presented for the first time. The results of the present investigation, together with earlier published data, show that the type strains of four species of the "Streptomyces griseoviridis" phenetic cluster differ in the composition and structure of their teichoic acids; thus, teichoic acids may serve as chemotaxonomic markers of the species.

The conversion of glucose to fructose at elevated temperatures, as catalyzed by soluble and immobilized xylose (glucose) isomerases from the hyperthermophiles Thermotoga maritima (TMGI) and Thermotoga neapolitana 5068 (TNGI) and from the mesophile Streptomyces murinus (SMGI), was examined. At pH 7.0 in the presence of Mg(2+), the temperature optima for the three soluble enzymes were 85 degrees C (SMGI), 95 degrees to 100 degrees C (TNGI), and >100 degrees C (TMGI). Under certain conditions, soluble forms of the three enzymes exhibited an unusual, multiphasic inactivation behavior in which the decay rate slowed considerably after an initial rapid decline. However, the inactivation of the enzymes covalently immobilized to glass beads, monophasic in most cases, was characterized by a first-order decay rate intermediate between those of the initial rapid and slower phases for the soluble enzymes. Enzyme productivities for the three immobilized GIs were determined experimentally in the presence of Mg(2+). The highest productivities measured were 750 and 760 kg fructose per kilogram SMGI at 60 degrees C and 70 degrees C, respectively. The highest productivity for both TMGI and TNGI in the presence of Mg(2+) occurred at 70 degrees C, pH 7.0, with approximately 230 and 200 kg fructose per kilogram enzyme for TNGI and TMGI, respectively. At 80 degrees C and in the presence of Mg(2+), productivities for the three enzymes ranged from 31 to 273. A simple mathematical model, which accounted for thermal effects on kinetics, glucose-fructose equilibrium, and enzyme inactivation, was used to examine the potential for high-fructose corn syrup (HFCS) production at 80 degrees C and above using TNGI and SMGI under optimal conditions, which included the presence of both Co(2+) and Mg(2+). In the presence of both cations, these enzymes showed the potential to catalyze glucose-to-fructose conversion at 80 degrees C with estimated lifetime productivities on the order of 2000 kg fructose per kilogram enzyme, a value competitive with enzymes currently used at 55 degrees to 65 degrees C, but with the additional advantage of higher fructose concentrations. At 90 degrees C, the estimated productivity for SMGI dropped to 200, whereas, for TNGI, lifetime productivities on the order of 1000 were estimated. Assuming that the most favorable biocatalytic and thermostability features of these enzymes can be captured in immobilized form and the chemical lability of substrates and products can be minimized, HFCS production at high temperatures could be used to achieve higher fructose concentrations as well as create alternative processing strategies.

A glucose isomerase enzyme, obtained from Streptomyces murinus , was produced by a fermentation process and subjected to a series of tests to investigate its safety in use and manufacture. It was not mutagenic (Ames test, using liquid culture) nor did it provoke chromosomal damage (rat bone marrow cytogenetics test). It did not contain (nor did the organism produce) antimicrobial activity or macrolidpolyene antibiotics. It had no teratogenic activity when administered to pregnant rats at 100 000 ppm in the diet. It was without effect upon rats when administered at this dietary concentration for 4 weeks. Dietary administration at 5000, 15 000 or 50 000 ppm to rats for 13 weeks resulted in nephrocalcinosis in females at all dosages (probably a physiological response to the altered calcium:phosphate ratio in the admixed diet) and status spongiosus in the brains of males receiving 50 000 ppm. As the finding of nephrocalcinosis in rats is generally agreed to be of no toxicological importance with regard to the use in man, the dietary concentration of 15 000 ppm was considered to be highest no-effect level. This level corresponds to an intake of some 1000 mg/kg/day, which represents approximately 8000 times the human intake based on a conservative estimation.

SAP, originally found as an aggregation factor of S. marcescens, was composed of about 75% protein and 25% sugar which consists of glucose, glucosamine, and galactosamine. SAP was stable against enzymatic digestion (37°C, 1 hr) by some proteinases and polysaccharide-hydrolyzing enzymes. The aggregation activity of the factor toward S. marcescens cells was inhibited by bovine serum albumin, ATP, and EDTA, and SAP activity was not restored by the addition of a sufficient amount of calcium ions except for the inhibition by EDTA. It was thought that these inhibitors have an effect on SAP itself or on the binding of SAP to the cells. The aggregation of S. marcescens cells by SAP was temperature- and calcium ion-dependent, and consists of two steps, which are the binding of SAP to the cells and subsequent cell aggregation. The first step proceeded at 37°C in the absence of calcium ions, but the second step required calcium ions.

The food enzyme is a glucose isomerase (d‐xylose aldose‐ketose‐isomerase; EC 5.3.1.5) produced with a non‐genetically modified Streptomyces murinus strain NZYM‐GA by Novozymes A/S. The glucose isomerase is intended only to be used in an immobilised form in glucose isomerisation for the production of high fructose syrups. Residual amounts of total organic solids are removed by the purification steps applied during the production of high fructose syrups using the immobilised enzyme; consequently, dietary exposure was not calculated. Genotoxicity tests did not raise a safety concern. Similarity of the amino acid sequence to those of known allergens was searched and no match was found. The Panel considered that, under the intended conditions of use, the risk of allergic sensitisation and elicitation reactions by dietary exposure cannot be excluded, but the likelihood to occur is considered to be low. Based on the data provided, the immobilisation process and the removal of total organic solids during the production of high fructose syrups, the Panel concluded that this food enzyme does not give rise to safety concerns under the intended conditions of use.

Organosulfur compound's functionality constitutes an essential class of therapeutic agents in current medicinal chemistry. Especially sulfonamides called sulfa drugs were performed as both chemotherapeutic agents and useful antibacterial derivatives developed for medicine. The sulfamides in the same family with the sulfonamides have similar biological activities. In our research, it was studied with some 3-imino-4-substituted-1, 2, 5-thiadiazolidine 1,1-dioxides (ISTDs- 4a-d, four samples) that are five-membered cyclosulfamides. These compounds were previously synthesized and structurally characterized. The goals of this study are to investigate minimum inhibition concentration (MIC) values and antibacterial effects of these ISTDs compounds on Bacillus subtilis NRRL B-209T, Escherichia coli ATCC®25922T, Micrococcus luteusNRRL B-1018T, Nocardia abscessus DSM 44432T, Nocardia cyriacigeorgica DSMZ 44484T, Pseudomonas aeruginosa NRRL B-2679T Staphylococcus aureus ATCC®6538T, Streptomyces murinus ISP 5091T., Organosülfür bileşiklerinin işlevselliği, mevcut tıbbikimyada önemli bir terapötik madde sınıfını oluşturur. Özellikle sülfa ilaçlaradı verilen sülfonamitler hem kemoterapötik ajanlar hem de tıp içingeliştirilen etkili antibakteriyel türevler olarak gerçekleştirilmiştir.Sülfonamidlerle aynı ailedeki sülfamitler benzer biyolojik aktiviteleresahiptir. Araştırmamızda, beş üyeli siklosülfamitler olan bazı 3-imino-4-ikameedilmiş-1,2,5-tiadiazolidin 1,1-dioksitler (ISTD'ler-4a-d, dört örnek) ileçalışılmıştır. Bu bileşikler daha önce sentezlenmiş ve yapısal olarakkarakterize edilmiştir. Bu çalışmanın amacı, Minimum inhibisyon konsantrasyon(MİK) değerlerini ve bu ISTD bileşiklerinin antibakteriyel etkilerini Bacillussubtilis NRRL B-209, Escherichia coli ATCC®25922, Micrococcus luteus NRRLB-1018, Nocardia abscessus DSM 44432, Nocardia cyriacigeorgica DSMZ 44484,Pseudomonas aeruginosa NRRL B-2679 Staphylococcus aureus ATCC®6538,Streptomyces murinus ISP 5091 üzerinde araştırmaktır.

The isomerization of glucose to fructose by immobilized glucose isomerase (IGI, produced from Streptomyces murinus and immobilized on silica) was conducted under two different conditions—microwave irradiation and conventional heating to compare their overall effects. It was found that compared with conventional heating, microwave irradiation significantly enhanced the activity of IGI and the effects of acceleration might be non-thermal microwave effect. Under the optimum conditions of microwave irradiation-assisted isomerization (magnesium ion concentration of 50 mM, 0.1 M pH 7.5 phosphate buffered saline (PBS) buffer, 70 °C, microwave power of 480 W, agitation speed of 150 rpm, glucose concentration of 0.8 M and 2% IGI based on the solution weight percentage), 45% yield of fructose could be achieved in 16 h, while only 43% yield of fructose was obtained until 24 h by using conventional heating. These results indicated that microwave irradiation might be a fast and efficient method for enzyme-catalyzed isomerization of glucose to fructose.

Plectosporium tabacinum root rot disease of white lupine is reported for the first time in Cairo Governorate provinces. Symptoms of the disease appeared on young seedlings as stunting, yellowing and wilting of the foliage. Rotted roots were first became light brown and the lesions progressively extended over the whole root system and became dark brown. Plants died when the whole root system had become infected. For successful biological control of the disease 70 rhizosphere actinomycetes were isolated by the use of normal standard isolation techniques. Three of these isolates were found to be strongly antagonistic against P. tabacinum in vitro. They also significantly reduced the incidence of white lupine root rot disease in soil infested with P. tabacinum in greenhouse trials. The three actinomycete isolates were identified as Streptomyces cyanoviridis, Streptomyces murinus and Streptomyces griseoplanus. Plectosporium tabacinum-Wurzelfaule der Weislupine (Lupinus termis Forsk.) und deren biologische Bekampfung durch Streptomyces spp. Es wird zum ersten Mal uber das Vorkommen der Plectosporium tabacinum-Wurzelfaule der Weislupine in den Cairo Governorate-Provinces berichtet. Bei jungen Samlingen zeigten sich Symptome der Krankheit als Zwergswuchsigkeit, Vergilbungen sowie Blattwelken aus. Die befallenen Wurzeln wurden zuerst hellbraun, die Lasionen breiteten sich progressiv uber das ganze Wurzelsystem aus und sie wurden dunkel braun. Die Pflanzen starben ab, nachdem das gesamte Wurzelsystem befallen war. Um die Krankheit erfolgreich biologisch zu bekampfen, wurden 70 Actinomyceten aus der Rhizosphare mit Hilfe von Standard-Isolationstechniken isoliert. Drei dieser Isolate zeigten eine starke in vitro Hemmung gegenuber P. tabacinum. In Gewachshausversuchen bewirkten diese Stamme eine signifikante Verminderung der Weislupinenwurzelfaule in mit P. tabacinum verseuchten Boden. Diese drei Actinomycet-Isolate wurden als Streptomyces cyanoviridis, S. murinus und S. griseoplanus bestimmt.

As a continuation of an ongoing study of DNA relatedness among red-spored streptomycetes, the homology between the four species comprising the Streptomyces fulvissimus phenotypic cluster (S. fulvissimus, Streptomyces aureoverticillatus, Streptomyces longispororuber and Streptomyces spectabilis) and the four species comprising the Streptomyces griseoviridis phenotypic cluster (S. griseoviridis, Streptomyces chryseus, Streptomyces daghestonicus and Streptomyces murinus) was measured spectrophotometrically from C0t05 determinations. All strains were also compared to 12 strains representing previously determined DNA-relatedness clusters in the Streptomyces lavendulae phenotypic cluster, including the type strain NRRL B-1230T. The strains segregated into 15 cluster groups at DNA relatedness >80%, including 10 single-membered clusters. S. griseoviridis and S. daghestonicus were synonymous, as were S. chryseus and S. longispororuber. S. spectabilis exhibited species-level homology with strain NRRL B-2402, which had been received as S. lavendulae. S. aureoverticillatus exhibited significant DNA relatedness to Streptomyces flavotricini. None of the strains from the S. fulvissimus or S. griseoviridis clusters exhibited significant homology to the type strain of S. lavendulae.

The properties of glucose isomerase (EC 5.3.1.5) and its synthetic applications are briefly reviewed and recent results with non-natural substrates are discussed. Commercially available immobilized glucose isomerase from Streptomyces murinus, previously discovered to accept d -glucose as well as d -fructose derivatives with modifications at C-3, C-5, and C-6, was also found to be an efficient catalyst for the conversion of 5,6-dimodified derivatives of d -glucose as well as 5-modified d -xylofuranose into the corresponding open-chain 2-ketoses. The equilibrium mixture in all but one case investigated favoured the respective ketose in ratios of 3:1 to 4:1. These results are in agreement with molecular modelling experiments suggesting that the free energies of the furanoid aldoses serving as starting materials are generally slightly higher than the values for the corresponding open-chain ketose. Dimerisation of the open-chain sugar derivatives was not observed.

Namibia is a semi-arid country with approximately 1% of arable land. Crop cultivation is profoundly challenged by nutrient-poor sandy soils combined with low water retention. To meet the increasing food demand, farmers resort to applying synthetic fertilisers and pesticides despite their environmental consequences. However, there is increasing evidence that arid or semi-arid plant microbiomes offer an unexploited reservoir that is pivotal to plant health, growth, and development. Plant growth promoting bacteria (PGPB) are of increased interest as they offer sustainable alternatives to environmentally unfriendly and unsustainable chemical fertilisers. The present study aimed to isolate, identify, and characterise plant-associated bacteria from five drought-tolerant legumes grown in Namibia. Identification was done using 16S rRNA sequencing and bioinformatics. Plant growth-promoting (PGP) abilities were characterised based on exopolysaccharide production, antifungal activity, indole acetic acid production, phosphate solubilization, siderophore production, and bacterial nitrogen fixation. Using 16S Illumina metagenomic sequencing, this study characterised the plant microbiomes of the nodules, roots, rhizosphere, and seeds. Isolates identified from the roots and rhizosphere were from the Proteobacteria (72%), Actinomycetota (15%), Bacteroidetes (5%) and Firmicutes (8%) phyla and included known plant growth-promoting species such as Stenotrophomonas pavanii, Streptomyces murinus, and Enterobacter cloacae. Nodule endophytes were mostly from the phylum Firmicutes (88%). The identified genera include Bacillus, Priestia, Paenibacillus, Gottfriedia, Neobacillus, Lysinibacillus, Fictibacillus, and Brevibacillus. Characterisation found that rhizobacteria expressed more plant growth promoting traits compared to root endophytes. Siderophore production was observed iii in most root endophytes and rhizobacteria. The following isolates, CRhi10, CRhi15, MBRhi17, HR5, RMBRhi4, RMBRhi1

Description des proprietes biochimiques et fonctionnelles de cette nouvelle enzyme utilisee en fabrication de sirop de glucose a forte teneur en fructose