RESUMO
Abstracts@#This study aims to determine the importance of conserved GDN motif in domain III and GXGXG motif in domain VI in Nipah virus (NiV) L protein. Four mutated L genes produced in an earlier study were inserted individually into plasmid pCITE. Optimised transfection protocol was successful in transfecting these plasmids, two helper plasmids (coding for N and P protein), NiV minigenome containing chloramphenicol acetyltransferase (CAT) reporter gene and T7 promoter. Successful in vitro transcription/translation in the NiV minireplicon system was monitored by CAT expression. In conclusion, GXGXG motif was important in the NiV minireplicon system but change of GDN motif does not affect L protein.
RESUMO
In recent years, the study found that Porphyromonas gingivalis type Ⅸ secretion system (T9SS) is a novel protein secretion system, also known as Por secretion system (PorSS). Unlike the eight protein secretion systems found in the past, the system is a polyprotein complex found only in Bacteroides. The secreted proteins have both N- and C-terminus, where the former includes Sec-dependent type Ⅰ signals peptide, and the latter contains conserved domains (C-terminal conserved domain, CTD). Porphyromonas gingivalis T9SS includes proteins such as intima, outer membrane, cytoplasm, and cell cycle, including at least 34 proteins containing CTD. Porphyromonas gingivalis T9SS is involved in regulating associated virulence factors including gingivin, fimbriae, lipopolysaccharide, HBP35, CPG70 protein and peptidyl-arginine deiminase. These CTD-containing virulence proteins are localized by T9SS and then released to the extracellular domain, thereby destroying periodontal tissue. Therefore, this review summarizes the research progress on the T9SS of Porphyromonas gingivalis.
RESUMO
Objective To verify the antibacterial activity of the conserved domain derived from the novel human antimicrobial peptide-hGlyrichin .Methods Bioinformative analysis was performed and two peptides derived from hGlyrichin were synthesized which contained the conserved domain .Results Analysis of antimicrobial activities showed that these two peptides exhibited strong antibacterial activity which was inversely proportional to the length of the peptide within an eligible range.Despite the effective inhibition and killing of bacteria , the synthetic peptide segments had no hemolytic effect on human red blood cells .Conclusion These results indicate that a conserved domain exists in hGlyrichin , and that the peptides which contain this domain have strong antibacterial activity but are not toxic to human somatic cells .
RESUMO
Horizontal gene transfer (HGT) is the movement of genetic material between kingdoms and is considered to play a positive role in adaptation. Cryptosporidium parvum is a parasitic protozoan that causes an infectious disease. Its genome sequencing reported 14 bacteria-like proteins in the nuclear genome. Among them, cgd2_1810, which has been annotated as CysQ, a sulfite synthesis pathway protein, is listed as one of the candidates of genes horizontally transferred from bacterial origin. In this report, we examined this issue using phylogenetic analysis. Our BLAST search showed that C. parvum CysQ protein had the highest similarity with that of proteobacteria. Analysis with NCBI's Conserved Domain Tree showed phylogenetic incongruence, in that C. parvum CysQ protein was located within a branch of proteobacteria in the cd01638 domain, a bacterial member of the inositol monophosphatase family. According to Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway, the sulfate assimilation pathway, where CysQ plays an important role, is well conserved in most eukaryotes as well as prokaryotes. However, the Apicomplexa, including C. parvum, largely lack orthologous genes of the pathway, suggesting its loss in those protozoan lineages. Therefore, we conclude that C. parvum regained cysQ from proteobacteria by HGT, although its functional role is elusive.