1.Isolation and identification of porcine epidemic diarrhea virus strain LN-2015-1 and its S gene mutation analysis
Nannan WANG ; Huinuan WANG ; Shenyang GAO ; Xiaoping DONG ; Jing LI ; Wenjun LIU ; Quan LIU ; Ning LI ; Liying LIU ; Tiezhong ZHOU
Chinese Journal of Veterinary Science 2017;37(8):1457-1462
In order to understand the porcine epidemic diarrhea virus (PEDV) origin and variant characteristics in Liaoning province,diagnosed by PCR,separated by Vero cell,and identified by cell pathological observation,RT-PCR and S gene sequence analysis,1 PEDV strains (LN-2015-1) was successfully isolated from a pig farm of Liaoning province.Analysis of S gene sequence showed that compared withCV777 strain,there were the longest 9 bp insertion,6 bp deletion and 13 bp continuous mutation in addition to point mutation.There also were the longest 3 AA insert,2 AA deletion,and 3 AA or more continuous mutation.The epitope analysis showed that there were 16AA mutations in the 5 epitope regions.Homology analysis show that it had the highest sequence similarity of 99.2% with HB-HA2015 strain,higher sequence similarity of 98.5%-98.8% with the domestic and foreign representative strains isolated since 2010,and lower sequence similarity of 93.2%-95.6% with the traditional strain isolated before 2010;the phylogenetic analysis showed that LN-2015-1 was clustered into the same group with home and abroad variation strain in recent years,and formed a small subgroup with HB-HA2015 at the same time.The evolutionary distance was far from the traditional strains.
2.Effects of temperature and pH on the growth of H1N1 subtype of influenza A virus by surface-enhanced Raman spectroscopy.
Xiaoxiao JIA ; Yun LI ; Wenhui FAN ; Qinglan SUN ; Tiezhong ZHOU ; Wenjun LIN ; Jing LI
Chinese Journal of Biotechnology 2016;32(4):447-456
Surface enhanced Raman spectroscopy technology (SERS), using gold nanoparticles as a base, was developed for rapid and sensitive detection of virus strains. SERS can be used as a rapid and reliable method to distinguish the titers of viral replication. In the present study, we characterized H1N1 subtypes of influenza A virus strains in different conditions of pH or temperatures, while we analyzed data from SERS technology using gold nanoparticles as a base and cell cultures were employed to further confirm the data from virus strains. Origin8.0 was used to collect Raman spectra, smooth and homogenize data, and to contrast spectra. Our results indicated that the peaks of different virus strains in optimal environmental conditions (T=37 ℃/pH=7.2) reached ≥3 000. This criterion was verified by subsequent virological method. The present data indicate that the established SERS protocol can be used as a rapid and reliable method to distinguish the replication rate of virus, which can be further used in clinical samples.
Gold
;
Hydrogen-Ion Concentration
;
Influenza A Virus, H1N1 Subtype
;
growth & development
;
Nanoparticles
;
Spectrum Analysis, Raman
;
Temperature
;
Virus Cultivation
;
methods