Screening Novel Drugresistant Mutations in Mycobacterium tuberculosis Strains by Using the Amplicon Sequencing Method / 中国生物化学与分子生物学报

Tuberculosis is one of the seriously public problems. The increasing drug-resistant tuberculosis is the key problem for controlling tuberculosis. Rapid and accurate diagnosis is important for further treatment. In this study‚ a next-generation sequencing method based on amplicon sequencing was constructed to screen the mutations in 17 drug-resistant genes of five first-line anti-tuberculosis drugs. A total of 65 mutations were identified in 26 clinic drug-resistant tuberculosis strains‚ including 33 hotspot mutations‚ 9 rare mutations‚ and 23 novel mutations. The pathogenesis‚ conservation‚ and partial structures caused by 18 novel missense mutations were predicted. The results showed that 14 novel mutations showed high conservation in nine species. All these 14 mutations could change the partial structure of protein. According to the detection and analysis results of this study‚ it is speculated that these newly discovered mutations may be potential drug-resistant mutations. It is a rapid‚ accurate and comprehensive method for the detection of drug-resistant mutations in first-line drug-resistant Mycobacterium tuberculosis‚ which could identify hotspot and rare mutations together with novel mutations. The detection method may be used for clinical diagnosis and basic research.

The effects of the recommended prescription for COVID-2019-lung-spleen qi deficiency on in vitro SARS-CoV-2 replication and pro-inflammatory factors expression / 中国药理学通报

Aim To determine the antiviral and anti-inflammatory effects of the recommended prescription for COVID-2019-lung-spleen qi deficiency(4-1)against in vitro infection of SARS-CoV-2 and common coronaviruses.Methods The main chemical substances of 4-1 were analyzed by LC-MS.The toxicity and antiviral effects of of 4-1 were detected by MTT and by CPE assay, respectively.The viral loads in cell supernatant and the expression of inflammatory factors induced by viral infection were determined by qRT-PCR.Results The recommended prescription 4-1 contained 94 chemical compounds, including flavonoids, steroids, sesquiterpenoids, and so on.The range of selection indexes for SARS-CoV-2 and common coronaviruses was 8.44±0.4952.26±2.3.This prescription could inhibit the proliferation of SARS-CoV-2, the expression of ACE2 and S mRNA, and down regulate IL-1α and CCL-5/RANTES at 10, 5, and 2.5 g•L-1 doses.Further, at doses of 20, 10 and 5 g•L-1, it could inhibit the proliferation of three common coronaviruses and suppress the overexpression of IL-6, CXCL-8/IL-8, CXCL-10/IP-10, TNF-α, IFN-α, CCL-2/MCP-1, MIG and CCL-5/RANTES induced by OC43/229E infection.The inhibitory effects were dose-dependent.Conclusions The prescription 4-1 has antiviral and anti-inflammation effects against multiple coronaviruses.This study provides the research basis for the treatment of common respiratory viral infections and emerging infectious diseases such as COVID-19 by using traditional Chinese medicine.

The homology analysis of ACE2 gene and its distinct expression in laboratory and wild animals

Angiotensin-converting enzyme-2 (ACE2) has been recognized as an entry receptor of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) into the host cells while bats has been suspected as natural host of SARS-CoV-2. However, the detail of intermediate host or the route of transmission of SARS-CoV-2 is still unclear. In this study, we analyze the conservation of ACE2 gene in 11 laboratory and wild animals that live in close proximity either with Bats or human and further investigated its RNA and protein expression pattern in wild bats, mice and tree shrew. We verified that the wild-bats and mice were belonged to Hipposideros pomona and Rattus norvegicus, respectively. ACE2 gene is highly conserved among all 11 animals species at the DNA level. Phylogenetic analysis based on the ACE2 nucleotide sequences revealed that wild bat and Tree shrew were forming a cluster close to human. We further report that ACE2 RNA expression pattern is highly species-specific in different tissues of different animals. Most notably, we found that the expression pattern of ACE2 RNA and protein are very different in each animal species. In summary, our results suggested that ACE2 gene is highly conserved among all 11 animals species. However, different relative expression pattern of ACE2 RNA and protein in each animal species is interesting. Further research is needed to clarify the possible connection between different relative expression pattern of ACE2 RNA and protein in different laboratory and wild animal species and the susceptibility to SARS-CoV-2 infection.