This study aims to investigate the epidemic variation of porcine circovirus type2(PCV2)and its distribution in swine farms in Henan Province from 2022 to 2023.In this study,1 206 pig blood samples from 18 urban scale swine farms,and 318 pigs and environmental samples from 2 PCV2-positive swine farms in Henan Province were detected by fluorescence quantitative PCR.ORF2 gene sequencing and genetic evolution analysis were performed on the positive samples.The results showed that the positive rate of PCV2 was 7.05％(85/1 206)in Henan Province,11.15％in western Henan Province and 3.03％in southern Henan Province.The positive rate of PCV2 in spring was 11.60％(67/576).A total of 31 ORF2 gene sequences were obtained,of which 23 were PCV2d(74.19％),6 were PCV2a(19.35％),one was PCV2b(3.23％)and one was PCV2c(3.23％).The results of amino acid sequence comparison showed that the mutation sites mainly concentrated on amino acids at positions 40-68 and 180-209.The total positive rate of pig farm sam-ples was 37.42％(119/318),and the positive rate of pig samples from different types of pig houses was 60.71％(34/56),45.83％(11/24),35.09％(20/57),and 33.33(3/9)in order from high to low.The positive rate of environmental samples from high to low was 56.36％(31/55)in feeding system,46.67％(7/15)in feces system,12.50(1/8)in decontamination area,11.11％(2/18)in living area,and no PCV2 was detected in ventilation system.The highest positive rate was 45.00％(9/20)for the tools in the house,7.14％(1/14)for the surface and sole of the clothes after leaving the house,and no PCV2 was detected on the surface and sole of the clothes before entering the house.In this study,the epidemiological investigation of PCV2 in Henan Province and its distribu-tion in swine farms were carried out,and the main circulating strains,seasons,regions and gene mutations of PCV2 in H enan Province were identified.The distribution and transmission routes of PCV2 in positive pig farms were preliminarily analyzed and summarized,which provided data basis and reference for effective prevention and control of PCV and the establishment of accurate bio-safety prevention and control measures.

This study aims to investigate the epidemic variation of porcine circovirus type2(PCV2)and its distribution in swine farms in Henan Province from 2022 to 2023.In this study,1 206 pig blood samples from 18 urban scale swine farms,and 318 pigs and environmental samples from 2 PCV2-positive swine farms in Henan Province were detected by fluorescence quantitative PCR.ORF2 gene sequencing and genetic evolution analysis were performed on the positive samples.The results showed that the positive rate of PCV2 was 7.05％(85/1 206)in Henan Province,11.15％in western Henan Province and 3.03％in southern Henan Province.The positive rate of PCV2 in spring was 11.60％(67/576).A total of 31 ORF2 gene sequences were obtained,of which 23 were PCV2d(74.19％),6 were PCV2a(19.35％),one was PCV2b(3.23％)and one was PCV2c(3.23％).The results of amino acid sequence comparison showed that the mutation sites mainly concentrated on amino acids at positions 40-68 and 180-209.The total positive rate of pig farm sam-ples was 37.42％(119/318),and the positive rate of pig samples from different types of pig houses was 60.71％(34/56),45.83％(11/24),35.09％(20/57),and 33.33(3/9)in order from high to low.The positive rate of environmental samples from high to low was 56.36％(31/55)in feeding system,46.67％(7/15)in feces system,12.50(1/8)in decontamination area,11.11％(2/18)in living area,and no PCV2 was detected in ventilation system.The highest positive rate was 45.00％(9/20)for the tools in the house,7.14％(1/14)for the surface and sole of the clothes after leaving the house,and no PCV2 was detected on the surface and sole of the clothes before entering the house.In this study,the epidemiological investigation of PCV2 in Henan Province and its distribu-tion in swine farms were carried out,and the main circulating strains,seasons,regions and gene mutations of PCV2 in H enan Province were identified.The distribution and transmission routes of PCV2 in positive pig farms were preliminarily analyzed and summarized,which provided data basis and reference for effective prevention and control of PCV and the establishment of accurate bio-safety prevention and control measures.

Diabetes mellitus is a typical metabolic disease.Its complications cause the main damage and lead to high mortality and disability eventually.The exact mechanism of diabetes is still unknown at present,and no radical cure of it is available.Therefore,the prevention of diabetes has become a priority.Metabolomics as a new technology can identify and measure the entire metabolic changes in the organism,and therefore has been widely applied to diabetes related studies with its enormous potential.

Artemisinin-based combination therapies (ACTs) are recommended to be the most effective therapies for the first-line treatment of uncomplicated falciparum malaria. However, artemisinin is often in short supply and unaffordable to most malaria patients, which limits the wide use of ACTs. Production of amorpha-4,11-diene, an artemisinin precursor, was investigated by engineering a heterologous isoprenoid biosynthetic pathway in Escherichia coli. The production of amorpha-4,11-diene was achieved by expression of a synthetic amorpha-4,11-diene synthase gene in Escherichia coli DHGT7 and further improved by about 13.3 fold through introducing the mevalonate pathway from Enterococcus faecalis. After eliminating three pathway bottlenecks including amorpha-4,11-diene synthase, HMG-CoA reducase and mevalonate kinase by optimizing the metabolic flux, the yield of amorpha-4,11-diene was increased by nearly 7.2 fold and reached at 235 mg/L in shaking flask culture. In conclusion, an engineered Escherichia coli was constructed for high-level production of amorpha-4,11-diene.
Alkyl and Aryl Transferases ; genetics ; Antimalarials ; metabolism ; Artemisinins ; metabolism ; Enterococcus faecalis ; genetics ; Escherichia coli ; genetics ; metabolism ; Metabolic Engineering ; methods ; Phosphotransferases (Alcohol Group Acceptor) ; metabolism ; Sesquiterpenes ; metabolism ; Transformation, Bacterial

Capillary zone electrophoresis (CZE) was used to monitor the whole unfolding process of bovine insulin resulted from the dithiothreitol (DTT) reduction. An off-line matrix assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS) was employed to determine the molecular weight of the reaction products at the same time to confirm the observation results obtained by CZE. The structural change during the process of bovine insulin unfolding could be observed directly from the electropherogram and information of protein unfolding could be obtained simultaneously. The results indicated that as an effective tool of monitoring the conformational change of protein,the method of CZE was simple,quick,sensitive and lower sample consumption.