Streptomyces thermonitrificans sp.n., a thermophilic streptomycete

A new species of thermophilicStreptomyces has been isolated from a soil sample collected in Bombay. Its morphological characteristics and physiological behaviour have been studied in detail. It has thus been found to belong to Series XVI-Thermophilus of Waksman's scheme of classification (1961). Its similarity to and differences from a few known species are described. It has been designated asStreptomyces thermonitrificans.     

Streptomyces fukangensis sp. nov., a novel alkaliphilic actinomycete isolated from a saline-alkaline soil

An alkaliphilic actinobacterium, designated EGI 80050^T, was isolated from a desert soil sample of Xinjiang, north-west China, and characterized by a polyphasic approach. The isolate was observed to produce purple orange-yellow aerial mycelium and dark orange-yellow substrate mycelium on yeast extract-malt extract agar medium. Whole-cell hydrolysates of strain EGI 80050^T were found to contain ll-diaminopimelic acid as the diagnostic diamino acid, and galactose, glucose, rhamnose and mannose as the main sugars. The major fatty acids identified were C_16:0-iso (36.8 %), C_15:0-anteiso (17.3 %), 15:0-iso (13.2 %) and 14:0-iso (10.5 %). The predominant menaquinones detected were MK-9(H₆) and MK-9(H₈), while the characteristic polar lipids were identified as diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, phosphatidylinositol mannosides, phosphatidylmethylethanolamine and three unknown phospholipids. The G+C content of the genomic DNA was determined to be 67.9 mol%. Phylogenetic analysis based on 16S rRNA gene sequences affiliated the strain EGI 80050^T to the genus Streptomyces. Levels of 16 rRNA gene sequence similarities between strain EGI 80050^T and Streptomyces candidus NRRL ISP-5141^T, Streptomyces cremeus NBRC 12760^T, Streptomyces spiroverticillatus NBRC 12821^T, Streptomyces violaceorectus NBRC 13102^T, Streptomyces cinereoruber subsp. cinereoruber NBRC 12756^T were 96.7, 96.6, 96.6, 96.6 and 96.6 %, respectively. Based on the phenotypic, chemotaxonomic and phylogenetic data, strain EGI 80050^T is considered to represent a novel species of the genus Streptomyces, for which the name Streptomyces fukangensis sp. nov. (type strain EGI 80050^T = BCRC 16945^T = JCM 19127^T) is proposed.     

Phenotypic variation in Streptomyces sp. DSM 40537, a lipoteichoic acid producing actinomycete

Aims:  To reinvestigate the production of lipoteichoic acid (LTA) by the actinomycete strain Streptomyces sp. DSM 40537 (=ATCC 3351).
Methods and Results:  LTA was extracted and purified from strain Streptomyces sp. DSM 40537. The identification of the LTA was confirmed by Western blotting with a monoclonal antibody. During these studies, two stable phenotypic variants of DSM 40537 were obtained, one of which released a distinctive orange pigment. 16S rRNA gene sequencing of each variant yielded identical sequences and allowed phylogenetic analysis to be performed.
Conclusions:  Streptomyces sp. DSM 40537 was shown to exhibit stable morphological variation. The strain was confirmed to be a LTA-producing actinomycete and to belong to the Streptomyces albidoflavus cluster within the genus Streptomyces .
Significance and Impact of the Study:  These data provide important support for the hypothesis that the distribution of LTA is linked to that of wall teichoic acids and emphasizes the need to reinvestigate LTA distribution in actinomycetes.     

Streptomyces luteolifulvus sp. nov., a novel actinomycete isolated from soil in Nanjing,China

During the investigation of exploring potential sources of novel species and natural bioactives, a novel actinomycete, designated strain HIT-DPA4^T, was isolated from a soil sample, which was collected from Nanjing, Jiangsu Province, PR China and characterized using a polyphasic approach. On the basis of 16S rRNA gene sequence similarities and the result of phylogenetic analysis, strain HIT-DPA4^T was most closely related to Streptomyces cyaneus CGMCC 4.1671 ^T, and shared the highest sequence similarity of 98.76%. In addition, the cell walls of the species HIT-DPA4^T contained LL-diaminopimelic acid as the diagnostic diamino acid and the whole-cell hydrolysates were identified as glucose and ribose, and the principal phospholipids were found to be diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol mannoside and phosphatidylmonomethylethanolamine. MK-9(H₆) and MK-9(H₄) were predominant menaquinones; and C_16:0, anteiso-C_15:0 and C_15:0 as major cellular fatty acids of the organism HIT-DPA4^T. Gene Ontology database analysis and antiSMASH server predicted results displayed that strain HIT-DPA4^T was a promising classification units, which has various types of functions and contains multiple biosynthetic gene clusters with the similarity more than 80%. Multilocus sequence analysis (MLSA) of five housekeeping genes (atpD, gyrB, recA, rpoB and trpB) illustrated that Streptomyces luteolifulvus formed a separate branch in the genus Streptomyces. However, a combination of low level of DNA-DNA relatedness and physiological properties indicated that strain HIT-DPA4^T can be distinguished from its phylogenetically related species Streptomyces cyaneus CGMCC 4.1671 ^T. Moreover, gene synteny research could be further differed organism HIT-DPA4^T from similarity species. Therefore, the strain is concluded to represent a novel species of the genus Streptomyces, for which the name Streptomyces luteolifulvus sp. nov. is proposed. The type strain is HIT-DPA4^T (=?CGMCC 4.7558 ^T?=?TISTR 2751 ^T).

     

Streptomyces phytohabitans sp. nov., a novel endophytic actinomycete isolated from medicinal plant Curcuma phaeocaulis

A novel actinomycete, designated strain KLBMP 4601^T, was isolated from the root of the medicinal plant Curcuma phaeocaulis collected from Sichuan Province, south-west China. The strain produced extensively branched substrate and aerial hyphae that carried straight to flexuous spore chains. Chemotaxonomic properties of this strain were consistent with those of members of the genus Streptomyces. The cell wall of strain KLBMP 4601^T contained ll-diaminopimelic acid as the characteristic diamino acid. The major menaquinone was MK-9(H₄), with minor amounts of MK-9(H₆), MK-9(H₈) and MK-10(H₂). The major fatty acids were C_16:0, iso-C_16:0, C_18:1ω9c and C_16:1, iso G. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain KLBMP 4601^T belongs to the genus Streptomyces and is most closely related to Streptomyces armeniacus JCM 3070^T (97.9 %), Streptomyces pharmamarensis PM267^T (97.6 %) and Streptomyces artemisiae YIM 63135^T (97.5 %). The 16S rRNA gene sequence similarity between strain KLBMP 4601^T and other members of this genus were lower than 97.5 %. DNA–DNA hybridization studies of strain KLBMP 4601^T with the three closest species showed relatedness values of 36.3 ± 4.2 %, 27.3 ± 0.6 %, and 30.9 ± 2.5 %, respectively. On the basis of chemotaxonomic, phenotypic and genotypic characteristics, it is evident that strain KLBMP 4601^T represents a novel species of the genus Streptomyces, for which the name Streptomyces phytohabitans sp. nov. is proposed. The type strain is KLBMP 4601^T (=KCTC 19892^T = NBRC 108772^T).     

Alterations in normal fatty acid composition in a temperature-sensitive mutant of a thermophilic bacillus

A temperature-sensitive mutant of a thermophilic bacillus was isolated which was unable to maintain membrane integrity at high temperature. The mutant appeared to lose cytoplasmic contents, as indicated by a decrease in turbidity and cell refractivity, when shifted from a permissive (52° C) to a restrictive (65° C) temperature. Cell number remained fairly constant, however. At the approximate onset of the decline in turbidity, viability decreased and net synthesis of ribonucleic acid, deoxyribonucleic acid, and protein ceased. Both chloramphenicol and sucrose were effective in retarding the decline in turbidity at 65° C. An abnormal fatty acid composition at high temperature suggested that the lesion in the mutant involved lipid synthesis. The proportion of fatty acids with a high melting point (> 55° C) increased in the parent from 42% at 42° C to 69% at 65° C. Similar changes were not made by the mutant. An abnormal phospholipid composition was also observed in the mutant at 42° C and 52° C. However, at 58° C, the maximum growth temperature of the mutant, the proportion of major phospholipids (phosphatidylglycerol, phosphatidylethanolamine, and cardiolipin) was similar to the parent strain. The mutant's apparent loss of membrane stability at high temperature and its inability to regulate fatty acid and phospholipid composition in a normal manner suggested that (i) the temperature-sensitivity of the mutant may be a result of a defect in normal lipid metabolism at high temperature and (ii) the normal changes in fatty acid composition observed at increased growth temperatures may be an essential feature of thermophily.A preliminary report of this work was presented at the 73rd Annual Meeting of the American Society for Microbiology, Miami Beach, Florida, May 6–11, 1973.     

Streptomyces manipurensis sp. nov., a novel actinomycete isolated from a limestone deposit site in Manipur, India

A novel actinobacterium, designated MBRL 201(T), was isolated from a sample collected from a limestone quarry at Hundung, Manipur, India. The strain was characterized using polyphasic taxonomy. Comparison of the 16S rRNA gene sequence of strain MBRL 201(T) and other Streptomyces species showed sequence similarities ranging from 93.0 to 99.6 % and strain MBRL 201(T) showed closest similarities to Streptomyces virginiae NBRC 12827(T) (99.6 %) and Streptomyces cinnamonensis NBRC 15873(T) (99.6 %). The DNA relatedness between MBRL 201(T) and the type strains of S. virginiae NBRC 12827(T) and S. cinnamonensis NBRC 15873(T) were 44.5 and 35.6 % respectively. Strain MBRL 201(T) contained LL: -diaminopimelic acid (A(2)pm) as the diagnostic diamino acid, with glucose as the main sugar, while small amounts of galactose, glucose, mannose, rhamnose, ribose and xylose were also present in cell-wall hydrolysates. The major fatty acids identified were anteiso-C(15:0) (38.9 %), iso-C(15:0) (19.9 %) and anteiso-C(17:1) (14.7 %). The predominant menaquinones detected were MK-9(H(6)) and MK-9(H(8)), while the polar lipids were diphosphatidylglycerol, phosphatidylmethylethanolamine, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol and phosphatidylinositolmannosides, with other unknown phospholipids and lipids. The G+C content of the genomic DNA was 72.9 %. The phenotypic and genotypic data showed that strain MBRL 201(T) merits recognition as a representative of a novel species of the genus Streptomyces. It is proposed that the isolate should be classified in the genus Streptomyces as a novel species, Streptomyces manipurensis sp. nov. The type strain is MBRL 201(T) (=DSM 42029(T)?=?JCM 17351(T)).     

Production of a fibrinolytic enzyme by thermophilic Streptomyces species

A strong fibrin-specific fibrinolytic enzyme was purified from the cell-free spent culture broth of a thermophilic organism, Streptomyces megasporus SD5. The strain could produce 150 mg crude protein per litre of spent broth, with a specific activity of 80 IU (Plough units) per milligram, within 18 h of incubation at 55 °C in glucose yeast/extract/peptone (GYP) medium, pH 8.0. For production of the enzyme, the strain could utilize different carbon and nitrogen sources with a C:N ratio of ∼ 1:2. The enzyme was stable at a broad range of pH ranging from 5 to 9, and highly thermostable with 50% activity after storage at 60 °C for 6 months. The enzyme belonged to the serine endopeptidase group. In vitro clot lysis revealed that the enzyme was active at 37 °C. This revised version was published online in July 2006 with corrections to the Cover Date.     

Temperature-dependent lipid content and fatty acid composition of three thermophilic bacteria

The lipid content and fatty acid composition of a strain ofBacillus caldolyticus and of two facultative thermophiles (B. flavothermus and strain NZ-2) were analysed after growth at different temperatures. In all three strains the amount of membrane, as a fraction of total cellular dry mass, was found to increase with temperature, however, in varying degrees. Changes of lipid content and protein/lipid ratio inB. caldolyticus between 60°C and 100°C and in strain NZ-2 between 45°C and 70°C were minor; inB. f avothermus the alterations in the 50°C–70°C range were more pronounced. The same was found for changes observed in the phospholipid/total lipid and phospholipid/membrane ratios, and also in the amounts of individual phospholipids. The alterations of the fatty acid composition were most significant inB. caldolyticus, especially between 80°C and 95°C. In contrast, the main changes inB. flavothermus and NZ-2 were found to occur between 30°C and 50°C, and between 45°C and 60°C, respectively. Based on these data, strain NZ-2 could be characterized as the least andB. flavothermus as the most versatile of the three organisms.     

Altered fatty acid composition in regulatory mutants of Streptomyces cinnamonensis

Abstract cDNA-RNA liquid hybridization analysis was used to compare the RNA sequence homology between two members of the Nudaurelia β virus family, Trichoplusia ni virus ( T.ni V) and Dasychira pudibunda virus ( D.p V). Heterologous hybridization experiments demonstrated that these viruses shared little sequence homology. Using oligo(dT) chromatography and oligo(dT)_12–18 as a primer for cDNA synthesis it was shown that neither T.ni V nor D.p V RNA genomes possess a poly(A) tract at the 3' end.