Micron-sized magnetic particles currently find a wide range of applications in many areas including biotechnology, biochemistry, colloid sciences and medicine. In this study, magnetic poly(glycidyl methacrylate) microparticles were synthesized by providing a polymerization around Fe(II)-Ni(II) magnetic double salt. Adsorption of lysozyme protein from aqueous systems was studied with these particles. Adsorption studies were performed with changing pH values, variable amount of adsorbent, different interaction times and lysozyme amounts. The adsorption capacity of the particles was investigated, and a value of about 95.6 mg lysozyme/g microparticle was obtained. The enzyme activity of the immobilized lysozyme was examined and found to be more stable and reusable compared to the free enzyme. The immobilized enzyme still showed 80% activity after five runs and managed to maintain 78% of its initial activity at the end of 60 days. Besides, in the antimicrobial analysis study for six different microorganisms, the minimum inhibitory concentration value of lysozyme immobilized particles was calculated as 125 μg/mL like free lysozyme. Finally, the adsorption interaction was found to be compatible with the Langmuir isotherm model. Accordingly, it can be said that magnetic poly(GMA) microparticles are suitable materials for lysozyme immobilization and immobilized lysozyme can be used in biotechnological studies.

A novel actinobacteria, isolate A7024T, was isolated from commercial hazelnut orchard soil sample which was collected at Duzce, West Black Sea region, Turkey. A polyphasic taxonomic study was carried out to determine the status of this isolate. The phylogenetic tree reconstructed using the neighbour-joining algorithm based on 16S rRNA gene sequences indicated that isolate A7024T was positioned within the members of the genus Streptomyces with the highest sequence similarity (97.7 %) to Streptomyces cadmiisoli ZFG47T. The organism formed an extensively branched substrate and aerial hyphae which generated irregular rod-shaped spores with smooth-surfaces. The cell wall of strain A7024T contained ll-diaminopimelic. Glucose, mannose and ribose were detected as whole-cell sugars. Its polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, three unidentified phospholipids and three unidentified glycolipids. Major menaquinones were MK-9(H6) and MK-9(H4). The major cellular fatty acids were iso-C16 : 0, anteiso-C15 : 0 and anteiso-C17 : 0. Strain A7024T had a genome size of 9.0 Mb with a genome G+C content of 71.5 mol%. The low level of 16S rRNA gene similarity, 19.3 ± 2.3% digital DNA–DNA hybridization and 76.94 % average nucleotide identity values, as well as some different phenotypic characteristics allowed the strain to be distinguished from the closely related type strains. Therefore, it is concluded that strain A7024T represents a novel species of the genus of Streptomyces , for which the name Streptomyces coryli sp. nov. is proposed. The type strain is A7024T (=DSM 42066T=KCTC 29102T=NRRL B-24888T).

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Two novel Actinobacteria , designated strains YC419T and YC504T, were isolated from a sediment sample collected from Lake Yeniçağa, Bolu Province, Turkey. Chemotaxonomic and morphological characteristics of isolates were found to be typical of members of the genus Streptomyces . Phylogenetic analyses based on 16S rRNA gene sequences revealed that strain YC419T was most closely related to Streptomyces vastus NBRC 13094T (99.0 %) and ‘Streptomyces xiangluensis’ NEAU-LA29 (98.6 %), and strain YC504T was to most closely related to Streptomyces caldifontis NCCP-1331T (98.6 %) and Streptomyces indicus IH32-1T (98.0 %). The cell walls of the two strains contained ll-diaminopimelic acid as the diagnostic diamino acid and the whole-cell hydrolysates were glucose, mannose and ribose. The predominant menaquinones were MK-9(H8) and MK-9(H6) in both strains. The major polar lipids of strain YC419T were diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylinositol, while strain YC504T had a similar profile but lacking diphosphatidylglycerol. The G+C contents of the genomic DNAs were 69.6 and 70.3 mol% for strains YC419T and YC504T, respectively. The phenotypic and genotypic data indicated that these two strains were readily distinguished from one another and the type strains of the other species classified in the genus Streptomyces . Therefore, the strains are suggested to represent two novel species of the genus Streptomyces , for which the names Streptomyces ureilyticus sp. nov. and Streptomyces mesophilus sp. nov. are proposed. The type strains are YC419T (=DSM 102299T=KCTC 39757T) and YC504T (=DSM 102300T=KCTC 39756T), respectively.