EstS1, a newly identified thermostable esterase from Sulfobacillus acidophilus DSM10332, was heterologously expressed in Escherichia coli and shown to enzymatically degrade phthalate esters (PAEs) to their corresponding monoalkyl PAEs. The optimal pH and temperature of the esterase were found to be 8.0 and 70°C, respectively. The half-life of EstS1 at 60°C was 15 h, indicating that the enzyme had good thermostability. The specificity constant (k cat /K m ) of the enzyme for p-nitrophenyl butyrate was as high as 6,770 mM ؊1 s ؊1 . The potential value of EstS1 was demonstrated by its ability to effectively hydrolyze 35 to 82% of PAEs (10 mM) within 2 min at 37°C, with all substrates being completely degraded within 24 h. At 60°C, the time required for complete hydrolysis of most PAEs was reduced by half. To our knowledge, this enzyme is a new esterase identified from thermophiles that is able to degrade various PAEs at high temperatures.

A lipase-producing bacterium strain B68 screened from soil samples of China was identified as Pseudomonas fluorescens. With GenomeWalker, the open reading frame of lipase gene lipB68, encoding 476 amino acids, was cloned and expressed in Escherichia coli BL21 (DE3). By affinity chromatography, the recombinant LipB68 protein was purified to the purity of 95%. As a member of lipase subfamily I.3, LipB68 has a unique optimum temperature of 20 degrees C, which was the lowest in this subfamily. In chiral resolution, LipB68 effectively catalyzed the transesterification of both alpha-phenylethanol and alpha-phenylpropanol at 20 degrees C, achieving E values greater than 100 and 60 after 120 h, respectively. Among all the known catalysts in biodiesel production, LipB68 produced biodiesel with a yield of 92% after 12 h, at the lowest temperature of 20 degrees C, and is the first one of the I.3 lipase subfamily reported to be capable of catalyzing the transesterification reaction of biodiesel production. Since lipase-mediated biodiesel production is normally carried out at 35-50 degrees C, the availability of a highly active lipase with a low optimal temperature can provide substantial savings in energy consumption. Thus, this novel psychrophilic lipase (LipB68) may represent a highly competitive energy-saving biocatalyst.

A novel lipase gene (lipB52) was isolated directly from the genomic DNA of Pseudomonas fluorescens B52 with the genome-walking method, an effective method for isolating lipase gene from bacteria. There was an open reading frame (ORF) of 1854 bp, which encoded 617 amino acids. The lipase gene (lipB52) was cloned into expression vector pPIC9K and successfully integrated into a heterologous fungal host, Pichia pastoris KM71, and the recombinant Pichia pastoris were screened with a high throughput method. The recombinant was induced by methanol to secrete active lipase into the culture medium. The recombinant lipase LipB52 was also purified and characterized. The optimum temperature for the purified lipase LipB52 was 40 degrees C at pH 8.0. It exhibited better thermostability and pH stability than its homologs.

In recent years, accreditation standards for international engineering education have led to a dramatic rise in the use of outcome-based education at universities. In this system, enticing new undergraduate students to science and engineering, although challenging, is the first important step toward building students' career competencies. An ongoing effort to attract students to biotechnology was initiated 13 years ago in the School of Biotechnology at the East China University of Science and Technology in Shanghai. We describe the design and organization of the Microbe Competition, a program attracting a total of nearly 6,500 students as of 2018. In the competition, students need to pass the microbiology knowledge test, provide a practical experiment proposal related to the topic of competition, and finish the experiment under the supervision of teachers before getting final prizes. The competition develops students' competencies in acquiring and applying knowledge, problem solving, teamwork, communication, and experimental skills. By investigating students' feedback, we have been continuously improving the quality of competition to attract more students from the biotechnology major. We hope that by sharing our experience, we can help educators at other universities organize similar introductory activities on their own campuses.

Lincomycin is a lincosamide antibiotic produced by Streptomyces lincolnensis. Through mutagenesis by ethylmethansulfonate (EMS) and ultraviolet (UV) irradiation repeatedly, M2 was picked out in plate with glutamine and propylproline orderly. In 50-L stirred bioreactor, the production of lincomycin, fermented by M2, was increased to 8136 u/ml under the optimal condition as compared to original strain S. lincolnensis 07-5 (6634 u/ml). Two-dimensional gel electrophoresis (2-D GE) and mass spectrometry (MS)-shown LmbG, LmbI, and acetohydroxy acid isomeroreductase were remarkably synthesized in M2. The gene lmbG and lmbI are responsible for methylation in the lincomycin biosynthetic cluster, while acetohydroxy acid isomeroreductase contributes to stronger metabolic capability. Finally, we obtained a better strain for industrial production.