Purification and Biochemical Characterization of a Novel Thermostable Serine Protease from Geobacillus sp. GS53

Proteases account for approximately 60% of the enzyme market in the world, and they are used in various industrial applications including the detergent industry. In this study, production and characterization of a novel serine protease of thermophilic Geobacillus sp. GS53 from Balçova geothermal region, İzmir, Turkey, were performed. The thermostable protease was purified through ammonium sulfate precipitation and anion-exchange chromatography. The results showed that the protease had 137.8 U mg?1 of specific activity and optimally worked at 55 oC and pH 8. It was also active in a broad pH (4–10) and temperature (25–75 °C) ranges. The protease was highly stable at 85 °C and demonstrated relative stability at pH 4, 7, and 10. Also, the enzyme had high stability against organic solvents and surfactants; enzyme relative activity did not decrease below 81% upon preincubation for 10 min. Ca2+, Cu2+, and Zn2+ ions slightly induced protease activity. The protease was highly specific to casein, skim milk, Hammerstein casein, and BSA substrates. These results revealed that the protease might have a potential effect in a variety of industrial fields, especially the detergent industry, because of its high thermostability and stability to surfactants. © 2021, The Author(s), under exclusive licence to Springer Science+Business Media, LLC part of Springer Nature.The authors would like to thank Biotechnology & Bioengineering Research Center at ?zmir Institute of Technology for the facilities and technical support

A multicenter, retrospective study to evaluate the effect of preoperative stoma site marking on stomal and peristomal complications

PubMedID: 24807019Even though preoperative marking of the stoma area is considered important for the prevention of postoperative complications, not all healthcare institutions have universally adopted this practice. A multicenter, retrospective, descriptive study was conducted to determine the effect of stoma site marking on stomal and peristomal complications. The 1-year study included 748 patients (408 [54.5%] male, mean age 56.60 ± 16.73 years) from eight stomatherapy units in Turkey. Patient data, including age, gender, diagnosis, type of surgery, history of preoperative stoma site marking, person performing the marking, and postoperative complications, were obtained from patient records, abstracted, and analyzed. Cancer was the reason for the operation in 545 (72.9%) of the cases. In 287 patients (38.4%), the stoma and wound care nurse and/or surgeon marked the stoma area; this occurred 1 day before or on the day of surgery according to Wound Ostomy Continence Nurses Society and American Society of Colon and Rectal Surgeons recommendations. Stomal/ peristomal complications developed in 248 (33.2%) persons; the most frequently observed complications in patients were parastomal skin problems (136, 48.7%), mucocutaneous separation (52, 18.6%), and retraction (31, 11.1%). The rate of complications was higher among patients whose stoma site was not marked than among those whose stoma site was marked (22.9% and 46%, respectively; P < 0.001). The results of this study confirm the stoma area should be marked preoperatively in all planned surgical interventions in order to reduce the risk of postoperative complications. Additional prospective and experimental studies on effectiveness of preoperative stoma site marking should be conducted with larger sample groups