Roadmap on emerging concepts in the physical biology of bacterial biofilms: from surface sensing to community formation

Bacterial biofilms are communities of bacteria that exist as aggregates that can adhere to surfaces or be free-standing. This complex, social mode of cellular organization is fundamental to the physiology of microbes and often exhibits surprising behavior. Bacterial biofilms are more than the sum of their parts: single-cell behavior has a complex relation to collective community behavior, in a manner perhaps cognate to the complex relation between atomic physics and condensed matter physics. Biofilm microbiology is a relatively young field by biology standards, but it has already attracted intense attention from physicists. Sometimes, this attention takes the form of seeing biofilms as inspiration for new physics. In this roadmap, we highlight the work of those who have taken the opposite strategy: we highlight the work of physicists and physical scientists who use physics to engage fundamental concepts in bacterial biofilm microbiology, including adhesion, sensing, motility, signaling, memory, energy flow, community formation and cooperativity. These contributions are juxtaposed with microbiologists who have made recent important discoveries on bacterial biofilms using state-of-the-art physical methods. The contributions to this roadmap exemplify how well physics and biology can be combined to achieve a new synthesis, rather than just a division of labor

Data_Sheet_1_Mathematical modeling of mechanosensitive reversal control in Myxococcus xanthus.pdf

Adjusting motility patterns according to environmental cues is important for bacterial survival. Myxococcus xanthus, a bacterium moving on surfaces by gliding and twitching mechanisms, modulates the reversal frequency of its front-back polarity in response to mechanical cues like substrate stiffness and cell-cell contact. In this study, we propose that M. xanthus’s gliding machinery senses environmental mechanical cues during force generation and modulates cell reversal accordingly. To examine our hypothesis, we expand an existing mathematical model for periodic polarity reversal in M. xanthus, incorporating the experimental data on the intracellular dynamics of the gliding machinery and the interaction between the gliding machinery and a key polarity regulator. The model successfully reproduces the dependence of cell reversal frequency on substrate stiffness observed in M. xanthus gliding. We further propose reversal control networks between the gliding and twitching motility machineries to explain the opposite reversal responses observed in wild type M. xanthus cells that possess both motility mechanisms. These results provide testable predictions for future experimental investigations. In conclusion, our model suggests that the gliding machinery in M. xanthus can function as a mechanosensor, which transduces mechanical cues into a cell reversal signal.</p

Bacteria that glide with helical tracks.

Many bacteria glide smoothly on surfaces, despite having no discernable propulsive organelles on their surface. Recent experiments with Myxococcus xanthus and Flavobacterium johnsoniae show that both of these distantly related bacterial species glide using proteins that move in helical tracks, albeit with significantly different motility mechanisms. Both species utilize proton-motive force for movement. Although the motors that power gliding in M.&nbsp;xanthus have been identified, the F.&nbsp;johnsoniae motors remain to be discovered

Research on Users’ Privacy-Sharing Intentions in the Health Data Tracking System Providing Personalized Services and Public Services

The utilization of user privacy data in the health data tracking system (HDTS) offers numerous benefits for businesses and public services, contingent upon users’ privacy sharing intentions. However, previous research neglected users’ preferences for public services and focused mainly on personalized services. Additionally, traditional privacy calculus theory has a limited focus on data security, leaving gaps in understanding individual and societal aspects. This study aims to fill these gaps by examining the influence of risk perception and factors like potential loss expectations, perceived personalized service benefits, group value identification, perceived public service utility, and perceived privacy on privacy sharing intentions in the context of personalized and public services. The results indicate a positive relationship between individual privacy protection perception and data sharing intention, as well as a positive relationship between group value identification and perceived public service utility with individuals’ privacy sharing intentions. Moreover, this research uncovers the moderating effect of information type sensitivity on the impact of perceived privacy and perceived public service utility on privacy sharing intentions, while there is no moderating effect of information type sensitivity on the relationship between group value identification and privacy sharing intentions. We recommend improving individual privacy education, ensuring data use transparency, and fostering identification with common group values to increase users’ privacy sharing intentions

Methyl-Hispolon from Phellinus lonicerinus (Agaricomycetes) Affects Estrogen Signals in MCF-7 Breast Cancer Cells and Premature Aging in Rats

We studied Phellinus lonicerinus to determine the cytotoxic effect and the dual estrogenic activities of methyl-hispolon and their relation to estrogen signals in vivo and in vitro. The Glide scores of methyl-hispolonestrogen receptor alpha (ER alpha) and methyl-hispolon-ER beta docked complexes were -7.29 kcal/mol and -6.68 kcal/mol in docking simulations. Methyl-hispolon had a significant antiproliferative effect for estrogen-sensitive ER(+) MCF-7 cells in the absence of estrogen, and it exhibited dual estrogen activities. Methyl-hispolon increased the serum E-2 in rats with premature ovarian failure and fulfilled the estrogenic function in the uterus and ovary. Methyl-hispolon significantly inhibited the expression of Ras, AP1, ER alpha, C-myc, and cyclinD1, as well as their gene transcription in RL95-2 cells. The phosphorylation of ERK1/2 was inhibited by methyl-hispolon. Thus, methyl-hispolon has potential use in treating estrogen deficiency-related diseases, with good antitumor effects and estrogenic activity

Radix Puerariae and Fructus Crataegi mixture inhibits renal injury in type 2 diabetes via decreasing of AKT/PI3K

Abstract Background Radix puerariae (RP) is a herbal medicines for diabetes, mainly because of anti-oxidative, insulin resistance and hypoglycemic effect. Fructus crataegi (FC) also possesses strong antioxidant activity in vitro. This study focused on the effects of herbal mixture of RP and FC (RPFC) on renal protection through a diabetic rat model. Methods Type 2 Diabetic model was established with high fat diet followed by injecting rats a low dose of STZ (25 mg/kg body weight). Rats were randomly divided into five groups: normal, high fat diet, diabetes mellitus, high fat diet plus RPFC prevention, and RPFC prevention before diabetes mellitus. RPFC was given to rats daily by intragastric gavage. The blood bio-chemical index and renal pathological changes were examined. The later includes hematoxylin and eosin staining, periodic acid schiff staining, and Masson trichrome staining. Protein levels of were determined by Western blot and immunohistochemical staining. mRNA levels were detected by RT-PCR. Results Rats prevented with RPFC resulted in decreasing blood glucose with corresponding vehicle treated rats. Glomerulus mesangial matrix expansion, renal capsule constriction, and renal tubular epithelial cell edema were less severe following RPFC prevention. Moreover, RPFC prevention reduced protein levels of PI3K, AKT, α-SMA and collagen IV in the kidney of diabetic rats. Conclusion Combined prevention with RPFC may inhibit the PI3K/AKT pathway in the kidney, thereby prevent renal injury in diabetic rats