Interruption of the (p)ppGpp synthetase gene (rel) of Sorangium cellulosum So ce56 resulted in loss of ppGpp accumulation after norvaline treatment during exponential growth phase. The rel mutant ...failed to produce wild-type levels of the polyketides chivosazol and etnangien in production media. In wild-type cells expression of the chivosazol biosynthetic operon can be significantly increased by norvaline or α-methylglucoside. This induction does not occur in the rel mutant. The rel mutant also lost the capability to form multicellular fruiting bodies under nutrient starvation.
The genus Sorangium synthesizes approximately half of the secondary metabolites isolated from myxobacteria, including the anti-cancer metabolite epothilone. We report the complete genome sequence of ...the model Sorangium strain S. cellulosum So ce56, which produces several natural products and has morphological and physiological properties typical of the genus. The circular genome, comprising 13,033,779 base pairs, is the largest bacterial genome sequenced to date. No global synteny with the genome of Myxococcus xanthus is apparent, revealing an unanticipated level of divergence between these myxobacteria. A large percentage of the genome is devoted to regulation, particularly post-translational phosphorylation, which probably supports the strain's complex, social lifestyle. This regulatory network includes the highest number of eukaryotic protein kinase-like kinases discovered in any organism. Seventeen secondary metabolite loci are encoded in the genome, as well as many enzymes with potential utility in industry.
Background and Aim
Bioprosthetic surgical aortic valve replacement (SAVR) is increasingly adopted in younger patients. We aimed to analyze mid‐term follow‐up data after SAVR to assess the performance ...of the prosthesis.
Methods
Data were collected from a single‐center series of 154 patients, who underwent SAVR with a bioprosthetic heart valve with the RESILIA tissue at our Heart Centre in Siegburg. All procedural and midterm patient outcomes were documented.
Results
Patients had a mean age of 56.8 ± 9.9 years, 35.7% were female, and the mean logistic European system for cardiac operative risk evaluation (EuroSCORE) was 3.4 ± 3.6%. Diabetes (12.3%), atrial fibrillation (10.4%), and chronic obstructive pulmonary disease (COPD) (5.8%) were common comorbidities. The mean surgery duration was 163.8 ± 73.4 min, with the 23 mm (34.4%) and 25 mm (33.8%) heart valves being most frequently implanted. At 3‐year follow‐up, mean pressure gradient was 13.9 ± 5.9 mmHg, peak gradient was 23.6 ± 7.7 mmHg, and effective orifice area (EOA) was 1.9 ± 0.4 cm². No patient died during the operation, 3 (2.1%) patients within 30 days, and 4 (2.7%) thereafter with an overall mortality of n = 7. Of the surviving patients, 97.8% were in New York Heart Association (NYHA) class I/II and none had structural valve deterioration (SVD).
Conclusion
Results of our single‐center study indicate favorable procedural outcomes. The safety outcomes confirm preliminary earlier results of this novel bioprosthesis but include more patients and a longer midterm follow‐up.
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