scholarly journals The bacteriostatic effect and mechanism of berberine on Methicillin resistant Staphylococcus aureus in vitro

2020 ◽  
Author(s):  
Lei Wang ◽  
Fangfang Zhou ◽  
Minyi Xu ◽  
Pei Lu ◽  
Ming Lin ◽  
...  

Abstract Background: To observe the bacteriostatic effect of berberine (BBR) and BBR combined with gentamicin (GEN), levofloxacin (LEV) and amikacin (AMI) on Methicillin resistant Staphylococcus aureus (MRSA), while also exploring the bacteriostatic mechanism of BBR on MRSA. Methods: The minimal inhibitory concentration (MIC) of BBR, GEN, LEV and AMI on 26 clinical MRSA strains was determined by broth microdilution, while the MICs of BBR combined with GEN, LEV and AMI against MRSA were determined using a microdilution checkerboard. Time-killing curves were used to determine the kinetics of BBR combined with antibiotics for MRSA. We used conductivity tests to assess the changes in membrane permeability in response to BBR on MRSA, while also investigating the changes in MRSA morphology by transmission electron microscopy. RNA-sequencing was used to analyze the expression of differentially expressed genes in reference strain USA300 after its treatment with BBR at different concentrations.Results: The MICs range of BBR on 26 strains of MRSA was 32-256 µg/mL. BBR combined with GEN, LEV and AMI had obvious bacteriostatic effect on MASA. After co-culturing MRSA with BBR at 512 ug/mL, 64 ug/mL and 8 ug/mL, respectively, the electrical conductivity increased, compared with the control group, by 8.14%, 13.08% and 12.01%, respectively. Using transmission electron microscopy, we found that low concentration of BBR (8 ug/mL) had no significant effect on MRSA structure (keeping intact), medium concentration of BBR (64 ug/mL) thinned the cell wall of MRSA, while high concentration of BBR (512 ug/mL) induced the destruction and dissolution of MRSA cell wall structure and the leakage of bacterial contents, leading to bacterial lysis. RNA-sequencing results showed that there were 754 differentially expressed genes in the high concentration group compared with the normal control group. Compared with the low concentration group, there were 590 differentially expressed genes in the high concentration group. Compared with the control group, only 19 genes were differentially expressed in the low concentration group. The up-regulated genes are mainly related to the cell wall hydrolysis regulatory genes, while the down-regulated genes are mainly related to the serine protease family.Conclusions: BBR displayed an excellent bacteriostatic effect on MRSA. BBR combined with GEN and AMI significantly enhanced the bacteriostatic effect on MRSA, while BBR combined with LEV showed no significant change in the bacteriostatic effect on MRSA. BBR inhibited bacteria by destroying and dissolving the structure of MRSA cell wall. RNA-sequencing results further demonstrated that the expression of cell wall hydrolysis genes ssaA, lytM and virulence factor serine protease genes were significantly differentially expressed when high concentration BBR treated on MRSA.

2020 ◽  
Author(s):  
Lei Wang ◽  
Fangfang Zhou ◽  
Minyi Xu ◽  
Pei Lu ◽  
Ming Lin ◽  
...  

Abstract Background: To observe the bacteriostatic effect of berberine (BBR) and BBR combined with gentamicin (GEN), levofloxacin (LEV) and amikacin (AMI) on Methicillin resistant Staphylococcus aureus (MRSA), while also exploring the bacteriostatic mechanism of BBR on MRSA. Results: The MICs range of BBR on 26 strains of MRSA was 32-256 µg/mL. BBR combined with GEN, LEV and AMI had obvious bacteriostatic effect on MRSA. After co-culturing MRSA with BBR at 512 µg/mL, 64 µg/mL and 8 µg/mL, respectively, the electrical conductivity increased, compared with the control group, by 8.14%, 13.08% and 12.01%, respectively. Using transmission electron microscopy, we found that low concentration of BBR (8 µg/mL; 1/8 MIC) caused no significant damage to MRSA, and the bacterial structure of MRSA remained intact, while high concentration of BBR (512 µg/mL; 8 MIC) induced the destruction and dissolution of MRSA cell wall structure and the leakage of bacterial contents, leading to bacterial lysis. RNA-sequencing results showed that there were 754 differentially expressed genes in the high concentration group compared with the normal control group. Compared with the low concentration group, there were 590 differentially expressed genes in the high concentration group. Compared with the control group, only 19 genes were differentially expressed in the low concentration group. The up-regulated genes are mainly related to the cell wall hydrolysis regulatory genes, while the down-regulated genes are mainly related to the serine protease family. Conclusions: BBR displayed an excellent bacteriostatic effect on MRSA. BBR combined with GEN and AMI significantly enhanced the bacteriostatic effect on MRSA, while BBR combined with LEV showed no significant change in the bacteriostatic effect on MRSA. BBR inhibited bacteria by destroying and dissolving the structure of MRSA cell wall. RNA-sequencing results further demonstrated that the expression of cell wall hydrolysis genes ssaA, lytM and virulence factor serine protease genes were significantly differentially expressed when high concentration BBR treated on MRSA.


2019 ◽  
Author(s):  
Lei Wang ◽  
Fangfang Zhou ◽  
Minyi Xu ◽  
Wei Gong ◽  
Shuiying Ji

Abstract Background: To observe the bacteriostatic effect of berberine on MRSA, while also exploring the bacteriostatic mechanism of BBR on MRSA. Methods: The MIC of BBR, gentamicin, levofloxacin,amikacin was determined by broth microdilution, while the MICs of BBR combined with gentamicin, levofloxacin,amikacin against MRSA were determined using microdilution checkerboard. Time-killing test were used to determine the kinetics of BBR combined with antibiotics for MRSA. We used conductivity to assess the changes in membrane permeability in response to BBR on MRSA, while also investigating the changes in MRSA morphology by TEM. RNA-sequencing was used to analyze the expression of differentially expressed genes in USA300 after its treatment with BBR. Results: The MICs range of BBR on MRSA was 32-256 µg/mL. The range of FICIs of BBR combined with gentamicin, levofloxacin,amikacin were 0.53-1.06, 0.62-1.5, 0.16-1.25. After co-culturing MRSA with BBR at 512 ug/mL, 64 ug/mL,8 ug/mL, respectively, the conductivity of these group increased by 8.14%,13.08% and 12.01%, respectively. Using TEM, we found that low-concentration of BBR had no significant effect on MRSA structure, medium-concentration of BBR thinned the cell wall of MRSA, while high-concentration of BBR destroyed cell wall, leading to bacterial lysis. RNA-sequencing results showed that there were 754 differentially expressed genes in the high-concentration group compared with the control group, of which 561 genes were up-regulated and 193 genes were down-regulated. Compared with the low-concentration group, there were 590 differentially expressed genes, of which 402 genes were up-regulated and 188 genes were down-regulated. Compared with the control group, 19 genes were differentially expressed in the low-concentration group, of which 11 genes were up-regulated,8 genes were down-regulated. Conclusions: BBR displayed an excellent bacteriostatic effect on MRSA. BBR combined with antibiotics significantly enhanced the bacteriostatic effect on MRSA. BBR inhibited bacteria by destroying the structure of cell wall. RNA-sequencing results demonstrated that the expression of cell wall hydrolysis genes and virulence factor were significantly differentially expressed on MRSA.


2020 ◽  
Vol 98 (Supplement_3) ◽  
pp. 165-166
Author(s):  
Elisa B Carvalho ◽  
Letícia P Sanglard ◽  
Karolina B Nascimento ◽  
Javier M Meneses ◽  
Daniel R Casagrande ◽  
...  

Abstract Gestating cows have an increased nutrient demand to meet the needs of developing the fetus and the mid-gestation is a critical period for the fetal skeletal muscle development. The aim of this study was to evaluate the skeletal muscle transcriptome in the progeny as a function of the maternal protein nutrition during mid-gestation. Eleven Tabapuã cows and their male calves were used in this study. In the first third of gestation (0 to 100 days of gestation; dg), all cows were kept on pasture. From 100 to 200 dg, the control group (CTRL; 7 animals) received a basal diet achieving 5.5% crude protein (CP), whereas the supplemented group (SUPPL; 4 animals) received a basal diet plus protein supplementation (40% CP). After 200 dg, all animals received the same diet. Weaning was performed at 205 ± 7.5 days of age and animals were kept on pasture until reaching 240 days of age, when they were transferred to a feedlot. Muscle samples were collected at 260 days of age and RNA was extracted for RNA-seq analysis. Gene expression data was analyzed with a negative binomial model to identify (q-value ≤ 0.05) differentially expressed genes (DEG) between treatments. A total of 716 DEG were identified (289 DEG up-regulated and 427 down-regulated in SUPPL group; q-value ≤ 0.05). From the 10 most significant down-regulated DEG in the SUPPL group, two genes associated with apoptotic process were identified: MAPK8IP1 and GRINA, with log2 Fold-Changes (log2FC) of 1.04 and 0.49, respectively. From the 10 most significant up-regulated DEG in the SUPPL group, mTOR was identified, with log2FC=0.31. This is a well-known gene involved in muscle protein synthesis. In conclusion, maternal protein supplementation during mid-gestation affects the expression of genes related to energy metabolism and muscle development, which can lead to long-term impacts on production efficiency.


Genes ◽  
2020 ◽  
Vol 11 (7) ◽  
pp. 823
Author(s):  
Xiayi Liu ◽  
Xiaochen Wang ◽  
Jing Liu ◽  
Xiangyu Wang ◽  
Haigang Bao

The Tibet chicken (Gallus gallus) lives on the Qinghai–Tibet Plateau and adapts to the hypoxic environment very well. The objectives of this study was to obtain candidate genes associated with hypoxia adaptation in the Tibet chicken embryos. In the present study, we used the fixation index (Fst) and cross population extended haplotype homozygosity (XPEHH) statistical methods to detect signatures of positive selection of the Tibet chicken, and analyzed the RNA sequencing data from the embryonic liver and heart with HISAT, StringTie and Ballgown for differentially expressed genes between the Tibet chicken and White leghorn (Gallus gallus, a kind of lowland chicken) embryos hatched under hypoxia condition. Genes which were screened out by both selection signature analysis and RNA sequencing analysis could be regarded as candidate genes for hypoxia adaptation of chicken embryos. We screened out 1772 genes by XPEHH and 601 genes by Fst, and obtained 384 and 353 differentially expressed genes in embryonic liver and heart, respectively. Among these genes, 89 genes were considered as candidate genes for hypoxia adaptation in chicken embryos. ARNT, AHR, GSTK1 and FGFR1 could be considered the most important candidate genes. Our findings provide references to elucidate the molecular mechanism of hypoxia adaptation in Tibet chicken embryos.


2019 ◽  
Vol 85 (21) ◽  
Author(s):  
Liqin Kang ◽  
Jiangsheng Zhou ◽  
Rui Wang ◽  
Xingwei Zhang ◽  
Cuicui Liu ◽  
...  

ABSTRACT This study reports that a high concentration of the endo-β-1,3-glucanase ENG (200 μg ml−1) induced heat-inactivated stipe wall extension of Coprinopsis cinerea, whereas a high concentration of the extracellular β-glucosidase BGL2 (1,000 μg ml−1) did not; however, in combination, low concentrations of ENG (25 μg ml−1) and BGL2 (260 μg ml−1) induced heat-inactivated stipe cell wall extension. In contrast to the previously reported chitinase-reconstituted stipe wall extension, β-1,3-glucanase-reconstituted heat-inactivated stipe cell wall extension initially exhibited a fast extension rate that quickly decreased to zero after approximately 60 min; the stipe cell wall extension induced by a high concentration of β-1,3-glucanase did not result in stipe breakage during measurement, and the inner surfaces of glucanase-reconstituted extended cell walls still remained as amorphous matrices that did not appear to have been damaged. These distinctive features of the β-1,3-glucanase-reconstituted wall extension may be because chitin chains are cross-linked not only to the nonreducing termini of the side chains and the backbones of β-1,6 branched β-1,3-glucans but also to other polysaccharides. Remarkably, a low concentration of either the β-1,3-glucanase ENG or of chitinase ChiE1 did not induce heat-inactivated stipe wall extension, but a combination of these two enzymes, each at a low concentration, showed stipe cell wall extension activity that exhibited a steady and continuous wall extension profile. Therefore, we concluded that the stipe cell wall extension is the result of the synergistic actions of glucanases and chitinases. IMPORTANCE We previously reported that the chitinase could induce stipe wall extension and was involved in stipe elongation growth of the mushroom Coprinopsis cinerea. In this study, we explored that β-1,3-glucanase also induced stipe cell wall extension. Interestingly, the extension profile and extended ultra-architecture of β-1,3-glucanase-reconstituted stipe wall were different from those of chitinase-reconstituted stipe wall. However, β-1,3-glucanase cooperated with chitinase to induce stipe cell wall extension. The significance of this synergy between glucanases and chitinases is that it enables a low concentration of active enzymes to induce wall extension, and the involvement of β-1,3-glucanases is necessary for the cell wall remodeling and the addition of new β-glucans during stipe elongation growth.


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