Genomic Insights into the Pathogenicity and Drug-Resistance of a Bacillus cereus Isolated from Human Teeth.

Background: Bacillus cereus is a common bacterium found in the environment. Some strains can cause food poisoning, and very few can cause clinically severe infections, leading to death. Here, we characterized the genome sequence of B. cereus LIN78 isolated from teeth with deep caries and compared it with those of 25 other related species. Methods: Third-generation sequencing technology, bacteriological analyses, biochemistry, and mass spectrometry were applied to characterize the drug-resistance genes and virulence factors of B. cereus LIN78. Results: The complete genome sequence of B. cereus Lin78 consists of 5647 genes distributed on a circular chromosome, a 393 kbp plasmid, and 928 pseudogenes (37.4% of whole-genome DNA). The LIN78 genome contains 14 sets of 16s, 23s, and 5s ribosomal RNA operons; 106 tRNA genes, one tmRNA, 12 genomic islands, six prophases, 64 repeats; 37 antibiotic-resistant genes; and 1119 putative virulence genes, including enterotoxins and cytolysins. The B. cereus LIN78 genome carries multiple copies of non-ribosomal polypeptide synthetase (NRPS) and post-translationally modified peptides (RiPPs). Phylogenetic analysis of the 26 B. cereus strains showed that B. cereus LIN78 is evolutionarily closely related to B. thuringiensis ATCC 10792 and B. cereus ATCC 14579. Conclusion: The newly isolated B. cereus carries many virulence genes, including enterotoxins and hemolysins, similar to B. anthracis, and multiple antibiotic resistance genes. These findings suggest that the strain has a potential risk of causing disease. Our studies are vital for further exploration of the evolution of B. cereus, its pathogenic mechanisms, and the control and treatment of bacterial infections.

A Systematic Analysis Reveals the Prognostic and Immunological Role of Reptin/RUVBL2 in Human Tumors.

Reptin/RUVBL2 is involved in the remodeling of chromatin, DNA damage repair, and regulation of the cell cycle, all of which help to play essential roles in cancer. However, relevant pan-cancer analysis of Reptin is lacking. This study first investigated the potential oncogenic roles of Reptin and revealed a relationship between Reptin with clinicopathological characteristics and immune infiltration based on big data. Here, we showed that Reptin is overexpressed in many cancers. A significant association exists between the expression of Reptin and the prognosis of cancer cases. Reptin had a meaningful interaction with the immune infiltration of CD4+ Th1 cells and immune modulator genes in multiple cancer types. And negative correlation exists between Reptin and cancer-associated fibroblasts in BRCA, PRAD, TGCT, and THYM. A significant negative association exists between Reptin and regulatory T cells in TGCT and THCA. Moreover, Reptin is significantly associated with genomic heterogeneity, DNA mismatch repair genes, methyltransferase, and RNA modification genes in specific cancer types. Spliceosome, Hippo signaling pathway, DNA replication pathway, and acetyltransferase activity-associated functions were observed in the effect of Reptin on the tumor. This systematic analysis highlights Reptin as a vital cancer regulator among numerous genes and proved its potential prognosticator value and therapeutic target role for specific tumor types.

PAK5 is a potential target in myelodysplastic syndrome through interacting with LMO2 and GATA1.

Myelodysplastic syndrome (MDS) is a neoplastic heterogeneous and pre-leukemic disease with poor clinical outcome due to the failure of current chemotherapeutic strategies to target leukemic stem cells. Recently, we find that p21-activated kinase 5 (PAK5) overexpresses in MDS patients and leukemia cell lines. The clinical and prognostic value of PAK5 in MDS is unclear although it has anti-apoptosis ability and can promote cell survival and mobility in solid tumors. In this study, we find that LMO2 is co-expressed with PAK5 in the aberrant cells from MDS, and mitochondria-localized PAK5 can translocate into cell nucleus upon fetal bovine serum stimulation to interact with LMO2 and GATA1, which are important transcription regulators in hematological malignancies. Interestingly, without LMO2, PAK5 fails to bind GATA1 and facilitate GATA1 Ser161 site phosphorylation, indicating that PAK5 may be a key kinase in LMO2-associated hematopoietic diseases. Moreover, we find that PAK5 protein level in MDS is significantly higher than leukemia, and the data of 2095 leukemia samples from 'BloodSpot' database shows that PAK5 mRNA level in MDS is also increased obviously. Taken together, our findings suggest that PAK5-targeted strategies in clinical therapy have a potential value on MDS intervention.

Puerarin suppresses production of nitric oxide and inducible nitric oxide synthase in lipopolysaccharide-induced N9 microglial cells through regulating MAPK phosphorylation, O-GlcNAcylation and NF-κB translocation.

Microglial cells play a critical role in mediating central nervous system inflammatory processes. Activated microglial cells induced by proinflammatory factor, such as lipopolysaccharide (LPS), release many kinds of neurotoxic cytokines including reactive oxygen species (ROS) which contributes to the pathogenesis of neurodegenerative diseases. Puerarin, extracted from kudzu root, possesses the characteristic of neuroprotection, antioxidation and anticancer. In the present study, we observed that LPS induced over-production of nitric oxide (NO) and increased the level of intracellular ROS in N9 microglial cells, but it was inhibited by puerarin. Furthermore, treatment with puerarin on N9 cells suppressed the over-expression of inducible nitric oxide synthase (iNOS) induced by LPS which is implicated in intracellular O-linked ß-N-acetylglucosamine (O-GlcNAc) level, phosphorylation of mitogen-activated protein kinase (MAPK) and nuclear factor κB (NF-κB) signaling pathway. We also observed that the enhanced phosphorylation of p38, JNK and ERK1/2 in N9 cells induced by LPS were inhibited by puerarin, otherwise the down-regulation of O-GlcNAcylation level of protein in N9 cell induced by LPS was up-regulated by pretreatment with puerarin. These results indicate that puerarin effectively inhibits microglia activation induced by LPS through inhibiting expression of iNOS, production of NO and ROS which was mediated via regulating O-GlcNAcylation, phosphorylation of MAPK and NF-κB translocation.