FOOD MICROBIOLOGY
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2023
·
IF 5.3
Hongchen Zhang,Yujun Zhai,Kewei Chen,Hui Shi
Escherichia coli O157:H7 can recover from sublethally injured (SI) state, which causes threat of foodborne illness . Adhesion plays a key role in the carriage of pathogens in food . In this study, we investigated the adhesion ability of SI and recovered E. coli O157:H7 wildtype and its three pili-deficient mutants (curli, type 1 fimbriae , and type IV pili) on six food-related surfaces. Plate counting was used to determine adhesion population after washing and oscillating the surfaces. Spinach exhibited the stronger adhesion population of E. coli O157:H7 than the other fresh produces (p < 0.05). In addition, at least one key pili dominated adhesion on these surfaces, and curli was always included. The adhesion population and contribution of different types of pili were jointly affected by surface and physiological state. This can be attributed to high hydrophobicity and positive charge density on surface and different expression levels of csgB , fimA , fimC and ppdD in SI and recovered cells. Among glucose, mannose , maltose , fructose, lactose, and sucrose , addition of 0.5% mannose could reduce adhesion of cells at all physiological states on stainless steel. Overall, this research will provide support for controlling adhesion of SI and recovered E. coli O157:H7.
研究领域:
微生物学
·
食品安全
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产品关联
DOI
PubMed
高影响因子
mBio
·
2024
·Vol. 15
·期 6
·
IF 5.1
Xiaolong Guo,Hua Yu,Junzhi Xiong,Qian Dai,Yuanyuan Li,Wei Zhang,Xiping Liao,Xiaomei He,Hongli Zhou,Kebin Zhang
Pseudomonas aeruginosa is one of the most common nosocomial pathogens worldwide, known for its virulence, drug resistance, and elaborate sensor-response network. The primary challenge encountered by pathogens during the initial stages of infection is the immune clearance arising from the host. The resident macrophages of barrier organs serve as the frontline defense against these pathogens. Central to our understanding is the mechanism by which bacteria modify their behavior to circumvent macrophage-mediated clearance, ensuring their persistence and colonization. To successfully evade macrophage-mediated phagocytosis, bacteria must possess an adaptive response mechanism. Two-component systems provide bacteria the agility to navigate diverse environmental challenges, translating external stimuli into cellular adaptive responses. Here, we report that the well-documented histidine kinase, LadS, coupled to a cognate two-component response regulator, PA0034, governs the expression of a vital adhesin called chaperone-usher pathway pilus cupA. The LadS/PA0034 system is susceptible to interference from the reactive oxygen species likely to be produced by macrophages and further lead to a poor adhesive phenotype with scantily cupA pilus, impairing the phagocytosis efficiency of macrophages during acute infection. This dynamic underscores the intriguing interplay: as macrophages deploy reactive oxygen species to combat bacterial invasion, the bacteria recalibrate their exterior to elude these defenses.
研究领域:
微生物学
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免疫学
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致病机理
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分子生物学
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产品关联
DOI
PubMed
高影响因子
Nature Communications
·
2021
·Vol. 12
·期 1
·1-9
·
IF 14.919
Yang Yonggang,Wang Zegao,Gan Cuifen,Klausen Lasse Hyldgaard,Bonné Robin,Kong Guannan,Luo Dizhou,Meert Mathijs,Zhu Chunjie,Sun Guoping,Guo Jun,Ma Yuxin,Bjerg Jesper Tataru,Manca Jean,Xu Meiying,Nielsen Lars Peter,Dong Mingdong
Long-distance extracellular electron transfer has been observed in Gram-negative bacteria and plays roles in both natural and engineering processes. The electron transfer can be mediated by conductive protein appendages (in short unicellular bacteria such as Geobacter species) or by conductive cell envelopes (in filamentous multicellular cable bacteria). Here we show that Lysinibacillus varians GY32, a filamentous unicellular Gram-positive bacterium, is capable of bidirectional extracellular electron transfer. In microbial fuel cells, L. varians can form centimetre-range conductive cellular networks and, when grown on graphite electrodes, the cells can reach a remarkable length of 1.08 mm. Atomic force microscopy and microelectrode analyses suggest that the conductivity is linked to pili-like protein appendages. Our results show that long-distance electron transfer is not limited to Gram-negative bacteria.
研究领域:
微生物学
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生物技术
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环境科学
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DOI
PubMed
高影响因子
Science Advances
·
2024
·Vol. 10
·期 50
·
IF 11.7
Na Chen,Jing Xi,Na Du,Ruichen Shen,Rui Zhao,Wei He,Tianhuang Peng,Yanbing Yang,Yun Zhang,Lilei Yu,Weihong Tan,Quan Yuan
Programming precise and specific microbial intraspecies or interspecies interaction would be powerful for microbial metabolic regulation, signal pathway mechanism understanding, and therapeutic application. However, it is still of great challenge to develop a simple and universal method to artificially encode the microbial interactions without interfering with the intrinsic cell metabolism. Here, we proposed an extensible and flexible framework nucleic acid strategy for encoding the specific and precise microbial interactions upon self-assembly. With this spatial manipulation tool, we propose the microbial spatial heterogeneity and short-range interaction mechanism that the microbial assembly facilitates the gene expressions of the surface sensors including flagella and pili in Pseudomonas aeruginosa, leading to a more sensitive response to quorum sensing. The microbial interaction programming strategy proposed in this work is expected to provide a powerful and designable nanoplatform for better understanding of distance-dependent bacterial communication networks.
研究领域:
微生物学
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合成生物学
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纳米技术
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分子生物学
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产品关联
DOI
PubMed
高影响因子
BIOMATERIALS
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2020
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IF 10.317
Yang Wu,Guiyun Deng,Kai Jiang,Huajuan Wang,Zhiyong Song,Heyou Han
Nitric oxide (NO) is an important biological messenger involved in the treatment of bacterial infections, but its controlled and targeted release in bacterial infections remains a major challenge. Herein, an intelligent NO nanogenerator triggered by near-infrared (NIR) light is constructed for targeted treatment of P. aeruginosa bacterial infection. Since maleimide can recognize and attach to the pilus of T4P of P. aeruginosa , we adopt this strategy to achieve the accurate release of therapeutic drugs at the infection site, i.e., after maleimide targets Gram-negative bacteria, the [email protected] @Au-Mal nanogenerator will release NO and generate ROS in situ from the inorganic photosensitizer gold nanoparticles under NIR irradiation to achieve synergistic antibacterial effect. In vivo experiments proved that the bacterial burden on the wound was reduced by 97.7%. Additionally, the nanogenerator was shown to promote the secretion of growth factors, which play a key role in regulating inflammation and inducing angiogenesis . This strategy has the advantage of generating a high concentration of NO in situ to promote the transfer of more NO and its derivatives (N 2 O 3 , ONOO − ) to bacteria, thereby significantly improving the antibacterial effect. The multifunctional antibacterial platform has been demonstrated as a good carrier for gas therapy because of its simple and efficient gas release performance, indicating its great potential for the treatment of drug-resistant bacterial infections.
研究领域:
生物医学工程
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纳米技术
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药学
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传染病学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
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