Fellahi Soltana, Chibani Abdelwaheb, Feuk-Lagerstedt Elisabeth, Taherzadeh Mohammad J
Department of Biology, Faculty of Sciences of Nature and Life, Mostaganem University, Mostaganem, Algeria.
Swedish Centre for Resource Recovery, University of Borås, Borås, Sweden.
AMB Express. 2016 Dec;6(1):42. doi: 10.1186/s13568-016-0213-0. Epub 2016 Jun 30.
The Bacillus strain (CCUG 66887) has a high capacity to excrete keratinase with the ability to degrade both alpha- and beta keratin. In this study we aimed to show the characteristics of the keratinolytic protease and to identify its gene by using liquid chromatography-electrospray ionization tandem mass spectrometry methods (nanoHPLC-ESI-MS/MS) followed by Mascot data base search. The results showed that the enzyme in fact consists of two different keratinases, both with a molecular mass of 38 kDa. Further, DNA sequencing generated the open reading frame (ORF) of one of the genes (Ker1), and de novo genome sequencing identified the ORF of the second gene (Ker2). The two keratinase genes contain 1153 base pairs each and have a gene similarity of 67 %. In addition, the Bacillus strain was classified as Bacillus pumilus and its genes were annotated in the GeneBank at NCBI (accession: CP011109.1). Amino acid sequences alignment with known B. pumilus proteases indicated that the two keratinases of B. pumilus strain C4 are subtilisin-like serine proteases belonging to the Protease S8 family. Taken together, these result suggest the two keratinases as promising candidates for enzymatic processing of keratinous wastes in waste refinery.
该芽孢杆菌菌株（CCUG 66887）具有高分泌角蛋白酶的能力，能够降解α-角蛋白和β-角蛋白。在本研究中，我们旨在通过液相色谱-电喷雾电离串联质谱法（nanoHPLC-ESI-MS/MS），随后进行 Mascot 数据库搜索，来展示角蛋白分解蛋白酶的特性并鉴定其基因。结果表明，该酶实际上由两种不同的角蛋白酶组成，二者分子量均为 38 kDa。此外，DNA 测序产生了其中一个基因（Ker1）的开放阅读框（ORF），而从头基因组测序鉴定出了第二个基因（Ker2）的 ORF。这两个角蛋白酶基因各包含 1153 个碱基对，基因相似度为 67%。此外，该芽孢杆菌菌株被归类为短小芽孢杆菌，其基因在 NCBI 的 GeneBank 中进行了注释（登录号：CP011109.1）。与已知短小芽孢杆菌蛋白酶的氨基酸序列比对表明，短小芽孢杆菌 C4 菌株的这两种角蛋白酶是属于蛋白酶 S8 家族的枯草杆菌蛋白酶样丝氨酸蛋白酶。综上所述，这些结果表明这两种角蛋白酶有望成为废物精炼厂中角蛋白废物酶处理的候选酶。
