Draft Genome Sequence of Streptomyces phaeoluteigriseus DSM41896

The draft genome for the type strain Streptomyces phaeoluteigriseus DSM41896 (ISP 5182) is reported. It was classified as a member of the Streptomyces violaceusniger clade; however, a polyphasic study showed it was a separate species based on its distinct spore morphology and 16S rRNA sequence. The genome sequence confirms it as a separate species

Studies on relationships between actinophage and variation in Streptomyces: I. Morphology of phage production and lysis in a streptomycete carrying a temperate phage

The relationship of phage production to lysis and variation in a streptomycete carrying temperate phage was investigated. Macroscopically, the original isolate, S-77, produced cartilaginous mycelial growth characteristic of Streptomyces. Microscopic examination, however, showed that discrete portions of hyphae were lysed within 48 hours of growth. These lysed portions were widely spaced with the ghost hyphal walls intact so that the mycelial structure and sporogenous habit of the streptomycete were maintained. Variants occurred which ranged from essentially normal-appearing cultures, through lightly sporulated and friable intermediates, to completely asporogenous and mucid cultures.Filtration and electron microscope studies established the presence of phage and showed ghost areas in hyphae as sites of phage release. Phage was found in filtrates of all S-77 variants including the normal-appearing parent type. Incomplete phage particles consisting of collapsed head membranes and of tailless particles were also common. Soft colony types with numerous ghost areas released large amounts of phage. Perfect phage was difficult to find in macroscopically normal cultures where lysed areas were widely spaced. Both normal S-77 and soft variants are either lysogenic or "carriers," since host and phage coexist in an equilibrial state through repeated transfer.It is suggested that the striking variation in morphological and cultural characteristics observed in S-77 results from shifts in the host-phage equilibrium.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/32516/1/0000607.pd

Induction of diverse secondary metabolites in Aspergillus fumigatus by microbial co-culture

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Halophilic Actinomycetes in 1 Saharan Soils of Algeria: Isolation, Taxonomy and Antagonistic Properties

The diversity of a population of 52 halophilic actinomycetes was evaluated by a polyphasic approach, which showed the presence of Actinopolyspora, Nocardiopsis, Saccharomonospora, Streptomonospora and Saccharopolyspora genera. One strain was considered to be a new member of the last genus and several other strains seem to be new species. Furthermore, 50% of strains were active against a broad range of indicators and contained genes encoding polyketide synthetases and nonribosomal peptide synthetases

Effects of donor/recipient human leukocyte antigen mismatch on human cytomegalovirus replication following liver transplantation.

Background Natural immunity against cytomegalovirus (CMV) can control virus replication after solid organ transplantation; however, it is not known which components of the adaptive immune system mediate this protection. We investigated whether this protection requires human leukocyte antigen (HLA) matching between donor and recipient by exploiting the fact that, unlike transplantation of other solid organs, liver transplantation does not require HLA matching, but some donor and recipient pairs may nevertheless be matched by chance. Methods To further investigate this immune control, we determined whether chance HLA matching between donor (D) and recipient (R) in liver transplants affected a range of viral replication parameters. Results In total, 274 liver transplant recipients were stratified according to matches at the HLA A, HLA B, and HLA DR loci. The incidence of CMV viremia, kinetics of replication, and peak viral load were similar between the HLA matched and mismatched patients in the D+/R+ and D−/R+ transplant groups. D+/R− transplants with 1 or 2 mismatches at the HLA DR locus had a higher incidence of CMV viremia >3000 genomes/mL blood compared to patients matched at this locus (78% vs. 17%; P = 0.01). Evidence was seen that matching at the HLA A locus had a small effect on peak viral loads in D+/R− patients, with median peak loads of 3540 and 14,706 genomes/mL in the 0 and combined (1 and 2) mismatch groups, respectively (P = 0.03). Conclusion Overall, our data indicate that, in the setting of liver transplantation, prevention of CMV infection and control of CMV replication by adaptive immunity is minimally influenced by HLA matching of the donor and recipient. Our data raise questions about immune control of CMV in the liver and also about the cells in which the virus is amplified to give rise to CMV viremia

Taxonomy and chemical characterization of antibiotics of Streptosporangium Sg 10 isolated from a Saharan soil

A new actinomycete strain designated Sg 10, producing antimicrobial substances was isolated from an Algerian soil. Morphological and chemical studies indicated that strain Sg 10 belonged to the genus Streptosporangium. The comparison of its physiological characteristics with those of known species of Streptosporangium showed significant differences with the nearest species Streptosporangium carneum. Analysis of the 16S rDNA sequence of strain Sg 10 showed a similarity level ranging between 96.3% and 97.8% within Streptosporangium species, with S. carneum the most closely related. However, the phylogenetic analysis indicated that strain Sg 10 represent a distinct phyletic line suggesting a new genomic species. The antimicrobial activity of strain Sg 10 showed an antibacterial activity against Gram-positive bacteria as well as an antifungal one. Four active products were isolated from the culture broth using various separation procedures. On the basis of UV-VIS spectrometry, infrared spectroscopy and chemical revelations, the antibiotics were classified in the group of glycosylated aromatics

Durability of open repair of juxtarenal abdominal aortic aneurysms

ObjectiveAs branched/fenestrated endografts expand endovascular options for juxtarenal abdominal aortic aneurysms (JAAAs), long-term durability will be compared to that of open JAAA repair, which has not been documented in large contemporary series. The goal of this study was to assess the late clinical and anatomic outcomes after open JAAA repair.MethodsFrom July 2001 to December 2007, 199 patients underwent open elective JAAA repair, as defined by a need for suprarenal clamping. End points included perioperative and late survival, long-term follow-up of renal function, and freedom from graft-related complications. Factors predictive of survival were determined by multivariate analysis.ResultsThe mean patient age was 74 years, 71% were men, and 20% had baseline renal insufficiency (Cr >1.5). Thirty-seven renal artery bypasses, for anatomic necessity or ostial stenosis, were performed in 36 patients. Overall 30-day mortality was 2.5%. Four patients (2.0%) required early dialysis; one patient recovered by discharge. Two additional patients progressed to dialysis over long-term follow-up. There was one graft infection involving one limb of a bifurcated graft. Surveillance imaging was obtained in 101 patients (72% of survivors) at a mean follow-up of 41 ± 28 months. Renal artery occlusion occurred in four patients (3% of imaged renal arteries; one native/three grafts). Two patients (2.0%) had aneurysmal degeneration of the aorta either proximal or distal to the repaired segment, but there were no anastomotic pseudoaneurysms. Remote aneurysms were found in 29 patients (29% of imaged patients), 14 of whom had descending thoracic aneurysm or TAAA. Four patients underwent subsequent thoracic endovascular aneurysm repair (TEVAR). Actuarial survival was 74 ± 3.3% at 5 years. Negative predictors of survival included increasing age at the time of operation (relative risk [RR], 1.05; P = .01), steroid use (RR, 2.20; P = .001), and elevated preoperative creatinine (RR, 1.73; P = .02).ConclusionsOpen JAAA repair yields excellent long-term anatomic durability and preserves renal function. Perioperative renal insufficiency occurs in 8.5% of patients, but few of them progress to dialysis. Graft-related complications are rare (2% at 40 months); however, axial imaging revealed descending thoracic aneurysms in 14% of imaged patients, making continued surveillance for remote aneurysms prudent. These data provide a benchmark against which fenestrated/branched endovascular aneurysm repair (EVAR) outcomes can be compared

Taxonomy and chemical characterization of new antibiotics produced by Saccharothrix SA198 isolated from a Saharan soil

Actinomycete strain SA198, isolated from a Saharan soil sample of Algeria, exhibited antimicrobial activity against Gram-positive and Gram-negative bacteria, and phytopathogenic and toxinogenic fungi. The morphological and chemotaxonomic characteristics of the strain were consistent with those of the genus Saccharothrix. Analysis of the 16S rRNA gene sequence of strain SA198 showed a similarity level ranging between 97.2 and 98.8% within Saccharothrix species, S. australiensis being the most closely related. Two new active products were isolated by reverse HPLC using a C18 column. The ultraviolet–visible (UV–VIS), infrared (IR), mass, and 1Hand 14C nuclear magnetic resonance (NMR) spectra showed that these products were new bioactive compounds. The minimum inhibitory concentrations of these antibiotics showed a strong activity against fungi and moderate activities against Gram-positive and Gram-negative bacteria

Actinopolyspora algeriensis sp. nov., a novel halophilic actinomycete isolated from a Saharan soil

A halophilic actinomycete strain designated H19T, was isolated from a Saharan soil in the Bamendil region (Ouargla province, South Algeria) and was characterized taxonomically by using a polyphasic approach. The morphological and chemotaxonomic characteristics of the strain were consistent with those of members of the genus Actinopolyspora, and 16S rRNA gene sequence analysis confirmed that strain H19T was a novel species of the genus Actinopolyspora. DNA–DNA hybridization value between strain H19T and the nearest Actinopolyspora species, A. halophila, was clearly below the 70 % threshold. The genotypic and phenotypic data showed that the organism represents a novel species of the genus Actinopolyspora for which the name Actinopolyspora algeriensis sp. nov. is proposed, with the type strain H19T (= DSM 45476T = CCUG 62415T)