IF 4.9 Q1 MICROBIOLOGY

Biofilm

Pub Date : 2025-12-01 Epub Date: 2025-11-05 DOI: 10.1016/j.bioflm.2025.100328

Albert Fuglsang-Madsen , Lasse Andersson Kvich , Nicole Lind Henriksen , Rasmus Kristensen , Jonas Rosager Henriksen , Anders Elias Hansen , Thomas Bjarnsholt , Tim Holm Jakobsen

Biofilms play a critical role in chronic bacterial infections, and new potent antimicrobials are urgently needed to address the escalating problem of antimicrobial resistance to existing therapies. To support the development of such therapeutics, there is a pressing need for biofilm models that better recapitulate the microenvironment of in vivo conditions. Existing in vitro assays, such as the widely used minimum biofilm eradication concentration (MBEC) assay, rely on liquid cultures that poorly reflect the structural and physiological characteristics of tissue-associated biofilms.

To address these limitations, we developed the Modified Crone's Model (MCM), a reproducible, semi-solid biofilm model that embeds bacteria in soft-tissue-like agar-based matrices. We established the MCM as a platform for evaluating the antimicrobial and specific anti-biofilm activity of novel and existing compounds. Biofilms grown in the MCM displayed consistent growth, in vivo-like morphology, and reduced variability compared to liquid-culture systems. Notably, antimicrobial susceptibility rankings in the MCM differed substantially from traditional assays, emphasizing that model-specific conditions can markedly affect the evaluation of antimicrobial potency and should be considered when selecting biofilm test systems.

Using the MCM, we screened a panel of therapeutic agents and identified two unsaturated fatty acids – cis-2-decenoic acid and cis-11-methyl-2-dodecenoic acid – as potent antibiotic potentiators with intrinsic anti-biofilm activity, undetectable in microbroth dilution assays. We further demonstrated the MCM's adaptability by replicating susceptibility profiles in biofilms grown on porcine bone tissue and implant surfaces, with no significant differences from agar-based biofilms.

The MCM offers a simple and reproducible platform for preclinical antimicrobial screening under semi-solid growth conditions that better reflect the spatial and diffusional constraints of biofilm-associated infections.

生物膜在慢性细菌感染中起着至关重要的作用，迫切需要新的有效的抗菌素来解决对现有疗法的抗菌素耐药性不断升级的问题。为了支持这种治疗方法的发展，迫切需要更好地概括体内微环境条件的生物膜模型。现有的体外检测，如广泛使用的最低生物膜根除浓度（MBEC）检测，依赖于液体培养，不能很好地反映组织相关生物膜的结构和生理特征。为了解决这些限制，我们开发了改良克罗恩模型（MCM），这是一种可重复的半固体生物膜模型，将细菌嵌入软组织样琼脂基基质中。我们建立了MCM作为评估新化合物和现有化合物的抗菌和特异性抗生物膜活性的平台。与液体培养系统相比，在MCM中生长的生物膜表现出一致的生长，具有体内样形态，并且变异性降低。值得注意的是，MCM中的抗菌药物敏感性排名与传统检测方法有很大不同，这强调了模型特异性条件可以显著影响抗菌效力的评估，在选择生物膜测试系统时应考虑到这一点。使用MCM，我们筛选了一组治疗药物，并确定了两种不饱和脂肪酸——顺式-2-十二烯酸和顺式-11-甲基-2-十二烯酸——作为有效的抗生素增强剂，具有内在的抗生物膜活性，在微肉汤稀释试验中检测不到。通过在猪骨组织和植入物表面生长的生物膜中复制敏感性谱，我们进一步证明了MCM的适应性，与琼脂基生物膜没有显著差异。MCM为半固体生长条件下的临床前抗菌药物筛选提供了一个简单且可重复的平台，可以更好地反映生物膜相关感染的空间和扩散限制。

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引用次数: 0

Dental plaque biofilm transforms host-derived β2-microglobulin into polymorphic fibrils for integration into the biofilm matrix 牙菌斑生物膜将宿主来源的β2微球蛋白转化为多形性原纤维，以整合到生物膜基质中

IF 4.9 Q1 MICROBIOLOGY

Biofilm

Pub Date : 2025-12-01 Epub Date: 2025-11-16 DOI: 10.1016/j.bioflm.2025.100331

Taiki Mori, Eisuke Domae, Mariko Hanaoka, Takeshi Into

Dental plaque is a polymicrobial biofilm formed on tooth surfaces despite continuous exposure to variable host-derived antimicrobial factors. To date, the underlying mechanisms remain nebulous. This study aimed to determine whether dental plaque biofilms affect the major salivary antimicrobial protein β₂-microglobulin (B2M). Immunostaining of human dental plaque specimens with an anti-B2M antibody revealed that B2M exists as elongated fibers, punctate structures, and amorphous aggregates. Fractionation of dental plaque suspensions revealed that B2M was present in both the soluble and insoluble fractions. B2M, which forms insoluble fibrils associated with dialysis-related amyloidosis, exhibited comparable fibril-forming properties in dental plaque. Immunostaining with a developed anti-B2M amyloid fibril antibody showed that fibrillar B2Ms (fB2Ms) were distributed throughout the dental plaque specimens. In vitro experiments using purified B2M demonstrated that environmental factors characteristic of dental plaque, specifically phosphate ions, bacterial short-chain fatty acids (acetic, butyric, lactic, and propionic acids), and divalent calcium and magnesium ions, significantly promoted fB2M formation. In a Streptococcus mutans biofilm model, native B2M transformed into fibrils only in the presence of these environmental factors, resulting in the loss of its antimicrobial activity and its incorporation into the biofilm matrix. The preformed fB2Ms increased S. mutans biofilm growth, decreased biofilm adhesion, and transformed the biofilm matrix architecture from a membranous to a reticulated organization, potentially facilitating biofilm dissemination. Dental plaque biofilms employed a specialized “molecular hijacking” strategy to counteract host defense mechanisms and ensure persistence through fibrillation. Our findings provide novel insights into biofilm pathogenesis, host-microbe interactions, and potential plaque control approaches.

牙菌斑是一种多微生物生物膜，尽管持续暴露于各种宿主衍生的抗菌因子，但仍在牙齿表面形成。到目前为止，潜在的机制仍然模糊不清。本研究旨在确定牙菌斑生物膜是否影响主要的唾液抗菌蛋白β2-微球蛋白（B2M）。用抗B2M抗体对人牙菌斑标本进行免疫染色，发现B2M以细长纤维、点状结构和无定形聚集体的形式存在。牙菌斑悬浮液的分离显示B2M存在于可溶性和不溶性组分中。B2M形成与透析相关淀粉样变性相关的不溶性原纤维，在牙菌斑中表现出类似的原纤维形成特性。抗b2m淀粉样蛋白原抗体免疫染色显示，纤维状b2m （fB2Ms）分布在牙菌斑标本中。体外纯化B2M实验表明，牙菌斑特征的环境因素，特别是磷酸盐离子、细菌短链脂肪酸（乙酸、丁酸、乳酸和丙酸）以及二价钙和镁离子，显著促进了fB2M的形成。在变形链球菌生物膜模型中，只有在这些环境因素存在的情况下，天然B2M才会转化为原纤维，导致其抗菌活性丧失，并与生物膜基质结合。预成型的fB2Ms增加了变形链球菌生物膜的生长，降低了生物膜的粘附，并将生物膜基质结构从膜状组织转变为网状组织，潜在地促进了生物膜的传播。牙菌斑生物膜采用一种专门的“分子劫持”策略来抵消宿主防御机制，并确保通过纤维性颤动持续存在。我们的发现为生物膜发病机制、宿主-微生物相互作用和潜在的斑块控制方法提供了新的见解。

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引用次数: 0

Ambroxol hydrochloride as an antibiofilm agent synergizes with tetracycline antibiotics against mature biofilms of multidrug-resistant Klebsiella pneumoniae 盐酸氨溴索与四环素类抗生素协同作用于多药耐药肺炎克雷伯菌成熟的生物膜

IF 4.9 Q1 MICROBIOLOGY

Biofilm

Pub Date : 2025-12-01 Epub Date: 2025-08-29 DOI: 10.1016/j.bioflm.2025.100315

TengLi Zhang , XunQin Gao , MengTing Liu , Chun Wen , Peng Jin , Hong Yao , XiWang Liu , YingLan Yu , Hao Shao , Lei Luo

Multidrug-resistant Klebsiella pneumoniae (MDR-KP) is a major pathogen responsible for hospital-acquired infections, associated with high morbidity and mortality. Biofilm formation plays a key role in the pathogenicity of MDR-KP and contributes significantly to its antibiotic resistance, substantially impairing the effectiveness of antimicrobial therapies. To enhance the efficacy of existing antibiotics, this study investigates a biofilm-targeting synergistic strategy inspired by the structural similarity between sputum and biofilm matrices. In this study, 87 clinical isolates of MDR-KP were initially screened for biofilm-forming capacity, and strong biofilm producers were selected to establish an in vitro model for systematic evaluation of the anti-biofilm efficacy of six mucolytic agents. Ambroxol hydrochloride (ABH) emerges as the optimal effective, disrupting biofilm structure at 0.7 mg/mL and achieving 50 % clearance within 8 h. ABH enhanced the anti-biofilm activity of tetracycline and doxycycline in vitro, reducing their IC₅₀ values by 98.9 % and 98.6 %, respectively, against preformed biofilms of MDR-KP compared to monotherapy. Additionally, the excellent physical and chemical compatibility between ABH and tetracycline or doxycycline provides a stable basis for in vivo co-administration. In vivo, the combination alleviates pulmonary inflammation, reduces bacterial load and inflammatory factor levels, and shows no tissue toxicity. In conclusion, ABH combined with tetracycline antimicrobials enhanced their efficacy against MDR-KP infections, especially biofilm-associated infections, in both in vitro and in vivo models, and possessed a favorable physicochemical compatibility and safety profile. These findings suggested that ABH-tetracycline therapy could represent a translationally promising and effective strategy for combating clinical MDR-KP infections.

耐多药肺炎克雷伯菌（MDR-KP）是导致医院获得性感染的主要病原体，与高发病率和死亡率相关。生物膜的形成在MDR-KP的致病性中起着关键作用，并对其抗生素耐药性起着重要作用，从而大大削弱了抗菌治疗的有效性。为了提高现有抗生素的疗效，本研究利用痰液和生物膜基质的结构相似性，研究了一种靶向生物膜的协同策略。本研究对87株MDR-KP临床分离株进行初步生物膜形成能力筛选，并选择生物膜生成能力强的菌株建立体外模型，系统评价6种解粘剂的抗生物膜效果。盐酸氨溴索（ABH）效果最佳，在0.7 mg/mL浓度时破坏生物膜结构，并在8 h内达到50%的清除率。与单药治疗相比，ABH增强了四环素和强力霉素的体外抗生物膜活性，其IC50值分别降低了98.9%和98.6%。此外，ABH与四环素或强力霉素之间良好的物理和化学相容性为体内共给药提供了稳定的基础。在体内，该组合可减轻肺部炎症，降低细菌负荷和炎症因子水平，且无组织毒性。综上所述，在体外和体内模型中，ABH联合四环素抗菌药物对耐多药kp感染，特别是生物膜相关感染的疗效增强，并且具有良好的理化相容性和安全性。这些发现表明，abh -四环素治疗可能是一种具有翻译前景的有效策略，可用于对抗临床耐多药kp感染。

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引用次数: 0

Dual red and near-infrared LED therapy inhibits MRSA biofilm in otitis media 双红色和近红外LED治疗抑制中耳炎中的MRSA生物膜

IF 4.9 Q1 MICROBIOLOGY

Biofilm

Pub Date : 2025-12-01 Epub Date: 2025-08-21 DOI: 10.1016/j.bioflm.2025.100314

Yoo-Seung Ko, Eun-Ji Gi, Sungsu Lee, Hong-Chan Kim, Hyong-Ho Cho

Otitis media (OM), particularly when caused by methicillin-resistant Staphylococcus aureus (MRSA), can become refractory due to biofilm formation, which contributes to resistance against conventional antimicrobial treatments. Photobiomodulation using light-emitting diode (LED) therapy has recently emerged as a promising non-antibiotic strategy for managing refractory infections by targeting biofilm-associated pathology. However, especially in the context of MRSA-induced OM, its therapeutic efficacy and underlying mechanisms remain incompletely elucidated. In this study, we established a rat model of OM by inoculating MRSA (5 × 10⁸ CFUs) into the middle ear via the tympanic membrane. Red and near-infrared (NIR) LED irradiation (655/842 nm; 163.2 W/m²; 30 min/day for 5 days) was administered 1 week after infection. Scanning electron microscopy revealed a marked reduction in MRSA biofilm structures, and biofilm biomass was significantly decreased, as assessed by crystal violet staining. Quantitative real-time polymerase chain reaction (qRT-PCR) analysis demonstrated significant downregulation of fib, icaB, icaC, and icaD, key genes crucial for bacterial adhesion and biofilm development. Histological assessment further showed decreased mucosal thickening and macrophage infiltration, supported by reduced ionized calcium-binding adapter molecule 1 (Iba1) expression. These findings suggest that dual red and NIR LED therapy effectively suppresses MRSA biofilm formation and inflammation in OM, indicating its potential as a novel non-antibiotic therapy for biofilm-associated OM that may help manage persistent or treatment-resistant cases in clinical settings.

中耳炎（OM），特别是由耐甲氧西林金黄色葡萄球菌（MRSA）引起的中耳炎，可由于生物膜的形成而变得难治性，这有助于对常规抗菌治疗产生耐药性。使用发光二极管（LED）治疗的光生物调节最近成为一种有前途的非抗生素策略，用于通过靶向生物膜相关病理来治疗难治性感染。然而，特别是在mrsa诱导的OM的背景下，其治疗效果和潜在机制仍未完全阐明。本研究通过中耳鼓膜接种MRSA (5 × 108 CFUs)，建立大鼠OM模型。感染1周后给予红色和近红外（NIR） LED照射（655/842 nm, 163.2 W/m2, 30分钟/天，持续5天）。扫描电镜显示MRSA生物膜结构明显减少，生物膜生物量明显减少，通过结晶紫染色评估。定量实时聚合酶链反应（qRT-PCR）分析显示，fib、icaB、icaC和icaD这些对细菌粘附和生物膜发育至关重要的关键基因显著下调。组织学评估进一步显示粘膜增厚和巨噬细胞浸润减少，这与离子钙结合适配器分子1 （Iba1）表达减少有关。这些发现表明，红色和近红外双LED治疗有效地抑制MRSA生物膜的形成和OM中的炎症，表明其作为一种新的非抗生素治疗生物膜相关OM的潜力，可能有助于治疗临床环境中的持续性或治疗耐药病例。

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引用次数: 0

Diverse microbial communities colonize biofilm carriers in moving bed and intermittent cleaning reactors for municipal and industrial wastewater treatment 不同的微生物群落定植在移动床和间歇清洗反应器中的生物膜载体上，用于市政和工业废水处理

IF 4.9 Q1 MICROBIOLOGY

Biofilm

Pub Date : 2025-12-01 Epub Date: 2025-11-20 DOI: 10.1016/j.bioflm.2025.100337

Eshetu Janka , Ram Prasath Alagappan , Dipaluk Das , Leif Arne Kjeldsberg , Shuai Wang , Tone Haugen , Alexander Wentzel

Conventional biofilm reactors are widely used for the removal of organic constituents and nutrients (i.e., nitrogen and phosphorus) in municipal and industrial wastewater treatment. Moving bed biofilm reactor (MBBR) and continuously flow intermittent cleaning reactor (CFIC) have been developed as more compact, small footprint, and highly efficient biofilm-based systems for wastewater treatment. However, despite the advancements in reactor technology, there is limited scientific information on the microbial composition of the biofilms in these systems. This study aimed to characterize and provide early insights into the microbial diversity of biofilms grown on biofilm carriers and liquid suspensions of the biofilm-based wastewater treatment systems. Microbial samples were collected from biofilm carriers and liquid suspension in four full-scale MBBR plants and two CFIC plants in Norway, all treating municipal and industrial wastewater. DNA was extracted from the samples and subjected to meta-barcode sequencing for taxonomic classification of microbial communities in each treatment plant. The results revealed significant variation in microbial compositions across treatment plants, influenced by wastewater characteristics, biofilm carrier types, and reactor operational characteristics. On the biofilm carriers, the dominant bacterial taxa included TM7-1 (Saccharibacteria), Burkholderiales, Clostridiales, Actinomycetales, Pseudomonadales, Rickettsiales, and Rhodobacteriales. In liquid suspensions, the dominant groups were Clostridiales, Methanosarcinales, Pseudomonadales, Flavobacteriales, and Rhodobacteriales. In conclusion, this study highlights the diverse microbial populations on biofilm carriers and liquid suspensions, which collectively contribute to the enhanced treatment efficiency of both MBBR and CFIC systems.

传统的生物膜反应器广泛用于去除城市和工业废水中的有机成分和营养物质（即氮和磷）。移动床生物膜反应器（MBBR）和连续流间歇净化反应器（CFIC）作为更紧凑、占地面积小、高效的生物膜废水处理系统已经得到了发展。然而，尽管反应器技术取得了进步，但关于这些系统中生物膜的微生物组成的科学信息有限。本研究旨在表征并提供早期的见解，以生物膜载体和生物膜废水处理系统的液体悬浮液上生长的生物膜的微生物多样性。在挪威的四个大型MBBR工厂和两个CFIC工厂中，从生物膜载体和液体悬浮液中收集微生物样本，这些工厂都处理城市和工业废水。从样品中提取DNA，并对每个处理厂的微生物群落进行元条形码测序进行分类。结果显示，受废水特性、生物膜载体类型和反应器运行特性的影响，不同处理厂的微生物组成存在显著差异。在生物膜载体上，优势菌群包括TM7-1 （Saccharibacteria）、伯克霍尔德菌属（Burkholderiales）、梭菌属（Clostridiales）、放线菌属（放线菌属）、假单胞菌属（pseudmonadales）、立克次体菌属（立克次体）和红杆菌属（Rhodobacteriales）。液体悬浮液中优势菌群为Clostridiales、Methanosarcinales、Pseudomonadales、Flavobacteriales和Rhodobacteriales。总之，本研究强调了生物膜载体和液体悬浮液上不同的微生物种群，它们共同促进了MBBR和CFIC系统处理效率的提高。

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引用次数: 0

10058-F4 Mediated inhibition of the biofilm formation in multidrug-resistant Staphylococcus aureus 10058-F4介导对多重耐药金黄色葡萄球菌生物膜形成的抑制作用

IF 5.9 Q1 MICROBIOLOGY

Biofilm

Pub Date : 2025-12-01 Epub Date: 2025-07-16 DOI: 10.1016/j.bioflm.2025.100307

Hiren Dodia , Suvendu Ojha , Puja Chatterjee , Tushar Kant Beuria

Antimicrobial resistance (AMR) is a global concern that undermines microbial disease treatment and prevention. WHO and World Bank's EcoAMR report predicts that AMR could cause 39 million deaths and $3.4 trillion in annual GDP losses by the year 2050. This is particularly critical with S. aureus, a cause of diverse infections like skin abscesses and pneumonia, where antibiotic resistance increases mortality and hinders treatment. Biofilms are one of the major causes of multi-drug resistance in S. aureus, and their inhibition can restore antibiotic sensitivity. In this study, through screening of the LOPAC drug library, we identified several compounds that exhibit biofilm inhibitory properties against multi-drug-resistant S. aureus without affecting its growth. The compound 10058-F4 was found to have the strongest anti-biofilm activity (>70 % inhibition) with minimal antibacterial effects (MIC 256 μg/mL); however, it showed no inhibitory effects on pre-existing biofilm. Further, the 10058-F4 treatment suppressed the expression of sarA, the biofilm master regulator, along with biofilm genes, such as icaA, fnb, nuc, and sspA. Additionally, the results showed that 10058-F4 synergistically enhanced the antibacterial activity of norfloxacin and tetracycline, indicating its potential use as an adjunct to the existing antibiotic treatments. While these findings suggest the potential of 10058-F4 for clinical use, further investigations are necessary to elucidate its mechanism of action and optimize its application in combination therapies.

抗菌素耐药性（AMR）是一个全球关注的问题，它破坏了微生物疾病的治疗和预防。世卫组织和世界银行的西非抗菌素耐药性报告预测，到2050年，抗菌素耐药性可能导致3900万人死亡，每年GDP损失3.4万亿美元。这对于金黄色葡萄球菌尤其重要，金黄色葡萄球菌是多种感染的原因，如皮肤脓肿和肺炎，抗生素耐药性会增加死亡率并阻碍治疗。生物膜是金黄色葡萄球菌耐多药的主要原因之一，抑制生物膜可恢复其对抗生素的敏感性。在本研究中，通过筛选LOPAC药物文库，我们发现了几种对多重耐药金黄色葡萄球菌表现出生物膜抑制特性而不影响其生长的化合物。化合物10058-F4抗生物膜活性最强（抑制率70%），抑菌作用最小（MIC为256 μg/mL）；但对已存在的生物膜无抑制作用。此外，10058-F4处理抑制了生物膜主调控因子sarA以及icaA、fnb、nuc和sspA等生物膜基因的表达。另外，10058-F4对诺氟沙星和四环素的抗菌活性有协同增强作用，提示其有可能作为现有抗生素治疗的辅助药物。虽然这些发现表明10058-F4具有临床应用的潜力，但需要进一步研究阐明其作用机制并优化其在联合治疗中的应用。

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引用次数: 0

Comparative transcriptomics analysis of the Oleidesulfovibrio alaskensis G20 biofilms grown on copper and polycarbonate surfaces 铜和聚碳酸酯表面生长的alaskensioledsulfovibrio G20生物膜的转录组学比较分析

IF 4.9 Q1 MICROBIOLOGY

Biofilm

Pub Date : 2025-12-01 Epub Date: 2025-08-06 DOI: 10.1016/j.bioflm.2025.100309

Priya Saxena , Dipayan Samanta , Payal Thakur , Vinoj Gopalakrishnan , Rajesh K. Sani

Sulfate-reducing bacterial (SRB) biofilms are prevalent across diverse environments, playing key roles in biogeochemical sulfur cycling while also contributing to industrial challenges such as biofouling and biocorrosion. Understanding the genetic and physiological adaptations of SRB biofilms to different surfaces is crucial for developing mitigation strategies. This study presents a comparative transcriptomic analysis of Oleidesulfovibrio alaskensis G20 biofilms grown on copper and polycarbonate surfaces, aimed at elucidating their differential responses at the molecular level. RNA sequencing revealed 1255 differentially expressed genes, with copper-grown biofilms exhibiting upregulation of Dde_1570 (flagellin; log2FC 2.31) and Dde_0831 (polysaccharide chain length determinant; log2FC 1.15), highlighting enhanced motility and extracellular polymeric substance production. Conversely, downregulated genes on copper included Dde_0132 (Cu/Zn efflux transporter; log2FC −3.37) and Dde_0369 (methyl-accepting chemotaxis protein; log2FC −1.19), indicating a metabolic shift and stress adaptation to metal exposure. Morphological analysis via SEM revealed denser biofilm clusters with precipitates on copper, whereas biofilms on polycarbonate were more dispersed. AFM analysis showed a 4.6-fold increase in roughness on copper (44.3 ± 3.1 to 205.89 ± 8.7 nm) and a 3.8-fold increase on polycarbonate (521.12 ± 15.2 to 1975.64 ± 52.6 nm), indicating surface erosion and structural modifications. Protein-protein interaction analysis identified tightly regulated clusters associated with ribosomal synthesis, folate metabolism, and quorum sensing, underscoring their role in biofilm resilience. Additionally, functional annotations of uncharacterized genes revealed potential biofilm regulators, such as Dde_4025 (cytochrome-like protein; log2FC 4.18) and Dde_3288 (DMT superfamily permease; log2FC 3.55). These findings provide mechanistic insights into surface-dependent biofilm formation, with implications for designing antifouling materials and controlling microbial-induced corrosion.

硫酸盐还原细菌（SRB）生物膜在各种环境中普遍存在，在生物地球化学硫循环中发挥关键作用，同时也为生物污染和生物腐蚀等工业挑战做出了贡献。了解SRB生物膜对不同表面的遗传和生理适应性对于制定缓解策略至关重要。本研究对生长在铜和聚碳酸酯表面的alaskensioledesulfovibrio G20生物膜进行了转录组学比较分析，旨在阐明它们在分子水平上的差异反应。RNA测序显示1255个差异表达基因，铜生长的生物膜显示Dde_1570(鞭毛蛋白；log2FC 2.31)和Dde_0831(多糖链长度决定因素；log2FC 1.15)，突出了增强的运动性和细胞外聚合物物质的产生。相反，铜上下调的基因包括Dde_0132 （Cu/Zn外排转运蛋白）；log2FC−3.37)和Dde_0369(甲基接受趋化蛋白；log2FC−1.19)，表明对金属暴露的代谢变化和应激适应。扫描电镜形态学分析表明，铜表面的生物膜簇密度更大，有沉淀，而聚碳酸酯表面的生物膜更分散。AFM分析表明，铜表面粗糙度增加4.6倍（从44.3±3.1到205.89±8.7 nm），聚碳酸酯表面粗糙度增加3.8倍（从521.12±15.2到1975.64±52.6 nm），表明表面侵蚀和结构改变。蛋白质-蛋白质相互作用分析发现了与核糖体合成、叶酸代谢和群体感应相关的紧密调控簇，强调了它们在生物膜弹性中的作用。此外，未表征基因的功能注释揭示了潜在的生物膜调节因子，如Dde_4025(细胞色素样蛋白；log2FC 4.18)和Dde_3288 (DMT超家族渗透酶；log2FC 3.55)。这些发现为表面依赖性生物膜形成提供了机理见解，对设计防污材料和控制微生物引起的腐蚀具有指导意义。

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引用次数: 0

Linoleic acid addition prevents Staphylococcus aureus biofilm formation on PMMA bone cement 添加亚油酸可阻止PMMA骨水泥上金黄色葡萄球菌生物膜的形成

IF 4.9 Q1 MICROBIOLOGY

Biofilm

Pub Date : 2025-12-01 Epub Date: 2025-08-07 DOI: 10.1016/j.bioflm.2025.100311

Linglu Hong , Karin Hjort , Dan I. Andersson , Cecilia Persson

Acrylic bone cement is widely used in vertebroplasty to treat osteoporosis-induced vertebral compression fractures. However, infection after vertebroplasty is problematic and previous work has suggested loading the bone cement with an antibiotic for prophylaxis. Linoleic acid (LA) has been investigated as a promising additive to improve the mechanical properties of bone cement for vertebroplasty, but LA could potentially also have an antibacterial effect. In this study, we evaluated the antibacterial properties of LA-loaded bone cement by comparing its antibiofilm properties with that of original bone cement through quantification of bacterial growth using viable cell count and scanning electron microscopy. The released monomer (MMA) concentration and the monomer minimum inhibitory concentration were determined to clarify the monomer's potential role in inhibiting bacterial growth. The LA release profile was measured, and a checkerboard assay was done to determine any synergistic effects of LA and the commonly used antibiotic gentamicin. Results show that LA-loaded bone cement could significantly inhibit Staphylococcus aureus biofilm formation, including gentamicin-resistant strains, but with limited effect on Escherichia coli. Furthermore, the released MMA did not have a significant influence on bacterial growth. The checkerboard assay results show that the LA and gentamicin combination could broaden the antibacterial spectrum and increase gentamicin efficacy. In conclusion, LA merits further investigation as an antibacterial agent in bone cement, alone or in combination with antibiotics.

丙烯酸骨水泥广泛应用于椎体成形术治疗骨质疏松性椎体压缩性骨折。然而，椎体成形术后的感染是有问题的，以前的工作建议在骨水泥中加入抗生素进行预防。亚油酸（LA）作为一种有前途的添加剂被研究用于改善椎体成形术骨水泥的力学性能，但LA也可能具有潜在的抗菌作用。在这项研究中，我们通过使用活细胞计数和扫描电镜对细菌生长进行量化，将负载la骨水泥的抗菌膜性能与原始骨水泥的抗菌膜性能进行比较，从而评估负载la骨水泥的抗菌性能。测定了释放单体（MMA）浓度和单体最低抑制浓度，以阐明单体在抑制细菌生长方面的潜在作用。测定了LA的释放谱，并用棋盘法测定了LA与常用抗生素庆大霉素的协同作用。结果表明，la负载骨水泥可以显著抑制金黄色葡萄球菌生物膜的形成，包括庆大霉素耐药菌株，但对大肠杆菌的作用有限。此外，释放的MMA对细菌生长没有显著影响。棋盘试验结果表明，LA与庆大霉素联用可拓宽抗菌谱，提高庆大霉素的药效。综上所述，LA作为骨水泥中的抗菌剂，无论是单独使用还是与抗生素联合使用，都值得进一步研究。

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引用次数: 0

S. aureus biofilm disruption using ultrasound and microbubbles: Influence of radiation force, bubble dynamics and biofilm growth conditions 利用超声和微泡破坏金黄色葡萄球菌生物膜：辐射力、气泡动力学和生物膜生长条件的影响

IF 4.9 Q1 MICROBIOLOGY

Biofilm

Pub Date : 2025-12-01 Epub Date: 2025-10-25 DOI: 10.1016/j.bioflm.2025.100327

Damien V.B. Batchelor , Anjali Lad , Kathryn L. Burr , Kristian Hollie , James R. McLaughlan , W. Bruce Turnbull , Jonathan A.T. Sandoe , Stephen D. Evans

Staphylococcus aureus is a human pathogen and a major cause of bloodstream infections, which can readily form biofilms on implanted medical devices. Here, we utilise a combination of lipid-shelled microbubbles (MBs) and ultrasound (US) to physically disperse the biofilm from the growth surface. The effects of two peak negative pressures (PNPs) and the direction of the acoustic radiation force (ARF) were evaluated. At 1.1 MHz, a clinically relevant frequency, and low PNP of 360 kPa, no significant biofilm dispersal occurred regardless of ultrasound (US) orientation. In contrast, at a high PNP of 2500 kPa, directing the ultrasound beam upward (US↑) pushed microbubbles (MBs) toward the biofilm, resulting in near-complete dispersal of the biofilm (94 ± 2 %) within the focal zone. Reversing direction to US↓, which pushes MBs away from the biofilm, reduced biofilm dispersal to 81 ± 3 %. Pre-treatment of the biofilm growth surface with fibrinogen or human plasma significantly altered the biofilm morphology and thickness, but did not affect the efficiency of ultrasound and microbubbles (US + MB)-mediated dispersal. Furthermore, multiple consecutive US + MB treatments could be applied to treat larger areas of biofilm without requiring MB replenishment between treatments. High-speed imaging was used to observe MB behaviour (e.g. translation and destruction) during US exposure. We revealed that the near instantaneous destruction of smaller MBs (∼1 μm) at high pressure did not induce significant biofilm dispersal and hypothesise that the translational motion of larger MBs (>10 μm) across the surface of the biofilm was the dominant mechanism behind biofilm dispersal.

金黄色葡萄球菌是一种人类病原体，也是血液感染的主要原因，它可以很容易地在植入的医疗器械上形成生物膜。在这里，我们利用脂质壳微泡（mb）和超声波（US）的组合来物理分散生长表面的生物膜。评价了两个峰值负压（PNPs）和声辐射力（ARF）方向对结构的影响。在1.1 MHz（临床相关频率）和360 kPa的低PNP下，无论超声（US）方向如何，都没有发生明显的生物膜分散。相比之下，在2500 kPa的高PNP下，引导超声波束向上（US↑）将微泡（mb）推向生物膜，导致生物膜在病灶区域内几乎完全分散（94±2%）。将方向转向US↓，使mb远离生物膜，使生物膜的分散率降低到81±3%。用纤维蛋白原或人血浆预处理生物膜生长表面可显著改变生物膜形态和厚度，但不影响超声和微泡（US + MB）介导的扩散效率。此外，多次连续的US + MB处理可以用于处理更大面积的生物膜，而不需要在处理之间补充MB。高速成像用于观察MB在美国暴露期间的行为（如平移和破坏）。我们发现，在高压下，较小的mb （~ 1 μm）的近瞬时破坏不会诱导显著的生物膜扩散，并假设较大的mb （>10 μm）在生物膜表面的平移运动是生物膜扩散背后的主要机制。

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引用次数: 0

Erratum to “Ecology of Legionella pneumophila biofilms: The link between transcriptional activity and the biphasic cycle” [Biofilm 7 100196] 对“嗜肺军团菌生物膜的生态学：转录活性与双相循环之间的联系”的勘误[Biofilm 7 100196]

IF 4.9 Q1 MICROBIOLOGY

Biofilm

Pub Date : 2025-12-01 Epub Date: 2025-06-25 DOI: 10.1016/j.bioflm.2025.100291

Ana Barbosa , Nuno F. Azevedo , Darla M. Goeres , Laura Cerqueira

引用次数: 0

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