The combined analysis improved diagnostic accuracy in children with bacterial and viral LRTIs.

Two human-infecting avian influenza viruses (AIVs), H7N9 and H10N8, have emerged in China, which further indicate that the H9N2 subtype of AIVs, as an internal gene donor, may have an important role in the generation of new viruses with cross-species transmissibility and pathogenicity. H9N2 viruses that contain such internal genes widely exist in poultry but are rarely reported in migratory birds. In this study, two strains of the H9N2 virus were isolated from fecal samples of migratory birds in 2014: one strain from Caizi Lake in Anhui Province and one from Chen Lake in Hubei Province of China. Nucleotide sequence analysis revealed high homology of all six internal genes of these two strains with the internal genes of the human H10N8 virus in Jiangxi Province, as well as with the human H7N9 virus. Phylogenetic analysis indicated a possible origin of these two strains from poultry in South China. Both of the two viruses tested could replicated in respiratory organs of infective mice without adaption, by both strains of the H9N2 AIVs from wild birds, suggesting their potential capacity for directly infecting mammals. Our findings indicate the existence of H9N2 viruses that contain internal genes highly homologous with human H10N8 or H7N9 viruses. Wild birds can contribute to the spread of the H9N2 virus that contains the “harmful” internal gene complex, leading to gene rearrangement with other influenza viruses and to the generation of new pathogenic viruses. Therefore, strengthening AIV surveillance in wild birds can promote an understanding of the presence and prevalence of viruses and provide scientific evidence for the prevention and control of AIVs and human-infecting AIVs.

Introduction: Tannase is a crucial enzyme that finds wide applications in the pharmaceutical industry, feed processing, and beverage manufacturing. Although extensive studies have been conducted on tannases from fungi and bacteria, reports on tannases exhibiting favorable pH stability are relatively limited.Methods: In this study, a tannin-degrading strain Debaryomyces hansenii was screened to induce tannase production, and the corresponding tannase coding gene TANF was successfully cloned and expressed in Yarrowia lipolytica. SDS-PAGE analysis revealed that the purified TanF tannase had a molecular weight of approximately 70 kDa.Results and Discussion: The enzyme demonstrated optimal activity at 40°C and retained over 80% of its activity in the range of 35°C–60°C. Of particular interest, TanF exhibited remarkable enzyme activity at pH 5.0 and retained more than 70% of its relative activity across a wide pH range of 3.0–8.0. Furthermore, TanF exhibited broad substrate specificity for gallate esters. The final gallic acid production by TanF from tannic acid achieved 18.32 g/L. Therefore, the excellent properties TanF has been demonstrated to be an efficient tool for the preparation of gallic acid.

Gene therapy emerged as important approach in treatment for many inborn disorders caused by genetic defects, as well as other diseases. This manuscript focused on Adeno-associated virus (AAV) based gene therapy to eye diseases. The paper firstly introduced the AAV vectors and the techniques of eye delivery, then summarized some tested genes that were used in past treatment to retinal degeneration disorders. Finally the paper discussed the updated optogenetics and its roles in AAV based gene therapy for eye diseases.

Purpose: L-Leucine is an essential amino acid for humans since it is only synthesized in fungi, bacteria, and plants. Its production has not been well documented as L-lysine and L-glutamic acid due to multivalent regulation and longer synthesis pathways. In Corynebacterium glutamicum, L-leucine synthesis is strongly regulated at α-isopropylmalate synthase (α-IMPS) node by the end product. Amino acid substitutions of the α-IMPS variant from strain ARTP-L04 were analyzed, and the α-IMPS variant was further characterized. To enhance the L-leucine production, the effect of α-IMPS variant was also evaluated.Methods: In the present study, construction of plasmid and recombination strain, protein expression and purification, enzymatic properties, fermentation, and amino acid analysis were performed.Results: Compared with leuA from wild-type strain ATCC 13032, 10 nucleotide exchanges were identified in the α-IMPS variant, leading to amino acid exchanges of Gly92Asp, Ile162Val, Gln494Arg, and Gly526Asp. Furthermore, the α-IMPS variant was expressed and characterized. It was found that the α-IPMS variant exhibited higher resistance to feedback inhibition by L-leucine. In the presence of 20 mM L-leucine, over 50% of α-IPMS variant activity was still observed. However, there was no significant difference in specific activity between the α-IPMS variant and wild-type α-IPMS. Therefore, the α-IPMS variant almost removed inhibition by L-leucine. Interestingly, co-expression of α-IPMS and AHAS both from strain ARTP-L04 could significantly enhance L-leucine production, accumulating 7.79 g/L L-leucine.Conclusions: Mutation that occurred in the α-IPMS variant played an important role in feedback resistance, almost removing feedback inhibition by L-leucine. In C. glutamicum, the expression of the α-IPMS variant could significantly enhance L-leucine production, especially when it was co-expressed with AHAS. Collectively, our findings provided valuable insights into further development in gene engineering.