کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
9602658 42761 2005 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Purification and characterization of a periplasmic laccase produced by Sinorhizobium meliloti
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی بیو مهندسی (مهندسی زیستی)
پیش نمایش صفحه اول مقاله
Purification and characterization of a periplasmic laccase produced by Sinorhizobium meliloti
چکیده انگلیسی
Sinorhizobium meliloti CE52G strain produces a periplasmic laccase that has been purified by a two-step procedure involving heat treatment and immobilized metal affinity chromatography (IMAC). The fraction with laccase activity retained its original activity after 24 h of incubation at pH between 4.0 and 8.0 and after 3 h of incubation at 70 °C, pH 7.2 and supplemented with 1.3 M (NH4)2SO4. It proved to be a homodimeric protein with an apparent molecular mass of 45 kDa each subunit and an isoelectric point of 6.2. CE52G laccase was inhibited by halides (NaF and NaCl), ions (Fe3+, Mn2+, and Cu2+), sulfhydryl organic compounds (β-mercaptoethanol and reduced glutathione), and electron flow inhibitors (NaCN and NaF). Laccase activity was strongly enhanced by (NH4)2SO4, Na2SO4, and K2SO4. The effects of all these agents, as well as the probability of a partially unfolding polypeptide chain to enhance the interaction between the substrate and the active site, are discussed. CE52G laccase is a pH- and thermo-stable protein with promising biotechnological applications.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Enzyme and Microbial Technology - Volume 36, Issues 5–6, 1 April 2005, Pages 800-807
نویسندگان
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