RESUMEN
This paper reviews the coronavirus species and post-infection symptoms of aquatic animals such as marine mammals, ferrets, fish, and waterfowl, analyzes the activity and transmission of coronaviruses in the aquatic environment, compares the homology of aquatic coronaviruses with SARS-CoV-2, and assesses the zoonotic risk. The results showed that aquatic animal coronaviruses were mainly α, γ, δ coronavirus and Alphaletovirus. SARS⁃CoV⁃2 is more similar to marine mammal coronavirus (51.90%-52.30%) and less similar to fish, mink, duck and goose coronavirus (43.30%-47.90%). The risk of transmission of coronaviruses carried by minks and marine mammals to humans is relatively greater, and from fish and waterfowl to humans is relatively small. By elaborating on the situation of coronavirus infection in aquatic animals, this paper is conducive to solving related issues such as the prevention and control of coronavirus epidemics, which is of great significance to ecosystems and public health.
RESUMEN
Objective To identify one runny mucoid-like Gram-negative bacteria with pink pigment isolated from clinical pus sample. Methods The pus sample was aseptically extracted from a deep lesions of one patient, then stored in Amies medium at room temperature for transportation. One sheep blood plate and one chocolate plate were used to detect the possible pathogens from the specimens. After inoculation, the plates were placed in a humidified incubator with 5% CO2 at 35 ℃. To identify the obtained isolates, we used the commercial Vitek2 and API systems, combining some traditional morphological examination and classical biochemical and physiological characteristics. For pure cultures, the cellular fatty acids were extracted, methylated, and determined by gas chromatography method. The 16S rRNA gene was amplified and sequenced by a commercial broad-spectrum PCR primers. The phylogenetic tree based on 16S rRNA gene was constructed by Mega 4.1 software using the neighbour-joining methods with 1 000 bootstrap replications. Results One runny mucoid-like Gram-negative bacterium, named K8756, was isolated both on sheep blood and chocolate plates after 72 h incubation. The API 20NE profile was 1245045 after a 3-day culture, which would be identified as Ochrobactrum anthropi with a good confidence of 98% probability. It was identified as Ralstonia pickettii and Bordetella bronchiseptica by VITEK 2 GN kits. However, further comparative 16S rRNA gene sequences showed that strain K8756 was closely related to the valid published Roseomonas mucosa MDA 5527 with 100% identity. Colonial morphologic features, phenotypic characteristics and major cellular fatty acid composition were also with high similarity to Roseomonas mucosa. Conclusions Strain K8756( = GIMCC 1.0030 ) is identified as Roseomonas mucosa by the polyphasic phenotypic and genotypic characteristics. The comparative analysis based on 16S rRNA gene sequences is a useful method for identifying the problematic and newly named bacteria.
RESUMEN
Objective To understand the primary structure and potential antigenic epitopes of antigen Pf332(Ag332) of P.falciparum iso late FCC1/HN.Methods Based on the published Pf332 gene sequence , nine pairs of primers were designed for the PCR amplification of the Pf332 gen e fragments from genomic DNA of P.falciparum isolate FCC1/HN. The amplified gene fragments were subcloned into pMD-18T vectors and sequenced. The sequences were aligned using DNAstar software to obtain the full-length sequence of the gene Pf332. The primary structure and sequence homology of Ag332 were analyzed by SAPS, Tmpred, SingalP and Blastn programs. Three fragments, R0, R1 and R2, cor responding to nt#9595-10083, nt#10339-10767 and nt#10855-11247 of Pf332 gene were subcloned into the eukaryotic expression vector pcDNA3-S separately. The Balb/c mice were immunized with pcDNA3-S-R0, pcDNA3-S-R1 and pcDNA3- S-R2 separately, and the expressions of the recombinant proteins were detected by immunohistochemistry assay. The protective immune responses elicited by DNA I mmunization were analyzed by ELISA and parasite growth inhibition tests in vitro .Results Nine Pf332 gene fragments were specifically amplif ied, subcloned into pMD-18T vectors and sequenced. Pf332 gene of the P.falci parum isolate FCC1/HN was 16,377 bp in length, encoding a protein of 5,458 ami no acids, about 615.28kDa. The Ag332 contains 17 regions of highly degenerated Glu-rich repeats, with 30.18% Glu in total amino acids of Ag332. Ag332 of P.falciparum isolate FCC1/HN and 3D7 exhibited 94.55 % homology in amino acid residues. The results of immunohischemistry assay showed that R0, R1 and R2 were expressed in mice muscle tissue. The amount of IgG antibody of the groups immu nized with pcDNA3-S-R0, pcDNA3-S-R1 and pcDNA3-S-R2 were higher than those of blank and pcDNA3 groups (P＜0.05). The result of parasite growth inhibition test showed that the immunized sera at 1∶5 dilution of groups of pcDNA3-S-R0, pcDNA3-S-R1 and pcDNA3-S-R2 had an incomplete inhibitor y effect on P.falciparum growth. Conclusion The antigen Pf332 is an large protein containing highly degenerated Glu-rich repeats. Pf332 gene fragments, R1 and R2 encoding potent antigenic epitope repeats.