1.Clinical characteristics and prognosis of immunotherapy for recurrent/metastatic nasopharyngeal carcinoma: a single-center retrospective analysis
WANG Haoqiang ; LIU Baiyang ; YANG Ning ; LIU Peng ; CHENG Donghai ; PENG Lijun ; WANG Xianci ; HUANG Xueqin ; DONG Enlai ; JIANG Yiming ; ZHOU Juan ; XIE Bo
Chinese Journal of Cancer Biotherapy 2026;33(1):84-90
[摘 要] 目的:探讨复发/转移性鼻咽癌(NPC)接受含PD-1单抗免疫治疗的临床特征和预后影响因素。方法:回顾性分析2019年3月至2024年7月期间南部战区总医院确诊的95例NPC患者的临床资料和外周血生化及免疫学指标。预后分析采用Kaplan-Meier曲线,组间比较使用Log-rank检验,采用Cox比例风险模型进行单因素和多因素分析。结果:95例患者中男性81例,女性14例,中位年龄49.72岁(16~74岁),Ⅳ期91例(95.79%),所有患者均采用免疫治疗,联合或不联合化疗方案治疗,中位无进展生存期(mPFS)为10.5个月,客观缓解率(ORR)70.53%,疾病控制率(DCR)89.47%,接受含铂治疗方案患者PFS相对更长,且差异有统计学意义。紫杉醇 + 顺铂 + 氟尿嘧啶(TPF)对比吉西他滨 + 顺铂(GP)和紫杉醇 + 顺铂(TP)显示出更长的PFS,但差异无统计学意义。不同PD-1单抗治疗组间的PFS未显示出有统计学意义的差异。单因素及多因素Cox回归分析结果显示,肿瘤复发状态、初始血浆EBV感染状态、治疗周期数、基线外周血SII是复发/转移性NPC患者接受PD-1抑制剂治疗疗效预测的独立相关因素(均P < 0.05),并且非复发患者、初始血浆EBV DNA阳性、接受 ≥ 4治疗周期、基线外周血SII < 772.81的患者接受PD-1抑制剂治疗预后相对更好。结论:在接受PD-1抑制剂治疗的复发/转移性NPC患者中,非复发患者、初始血浆EBV DNA阳性、≥ 4治疗周期且外周血SII < 772.81者PFS相对更长,可早期识别免疫治疗效果不佳患者并精准干预。
2.Pharmacodynamic Substances and Mechanisms of Xinglou Chengqi Tang in Treating Post-stroke Complications: A Review
Yujin ZHANG ; Xiangzhuo LIU ; Zhouyang CHEN ; Zihao SONG ; Xinyi LIU ; Yizhi YAN ; Chaoya LI ; Yingyan FANG ; Shasha YANG ; Xueqin CHENG ; Zhou XIE ; Sijie TAN ; Peng ZENG ; Yue ZHANG
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(1):327-337
Stroke is the leading cause of death and disability among adults in China, and its common complications include digestive system abnormalities, cognitive impairment, depression, stroke-associated pneumonia, and hemiplegia. The combination of traditional Chinese and Western medicine has great potential in treating post-stroke complications. Xinglou Chengqitang (XLCQT) is a representative prescription of alleviating the disease in the upper part by treating the lower part. It has definite therapeutic effect and high safety. Clinically, XLCQT is often used to treat stroke and its complications. However, the quantity and quality of clinical trials of XLCQT in treating post-stroke complications need to be improved. Additionally, since the basic research is weak, the material basis and multi-target mechanism for the efficacy of this prescription are unknown. This article reviews XLCQT in terms of the pharmacodynamic basis, medicinal properties, safety evaluation, and progress in clinical research and mechanisms in treating post-stroke complications. This article summarizes 22 key active ingredients of XLCQT in treating acute stroke complicated with syndrome of phlegm heat and fu-organ excess. Among these key active ingredients, resveratrol, kaempferol, luteolin, chrysoeriol, apigenin, (+)-catechin, and adenosine have good pharmacokinetic properties and high bioavailability. The mechanisms of XLCQT in treating post-stroke complications are complex, including inflammatory response, brain-gut axis, hypothalamic-pituitary-adrenal (HPA) axis, intestinal flora, neurotrophic factors, autophagy, oxidative stress, and free radical damage. This review helps to deeply understand the pharmacodynamic basis and mechanisms of XLCQT in treating post-stroke complications and provides a theoretical basis for the clinical application of XLCQT against post-stroke complications and the development of drugs.
3.Compilation Instruction for Pharmacovigilance Guidelines for Clinical Application of Oral Chinese Patent Medicines
Hongyan ZHANG ; Zhifei WANG ; Shuo YANG ; Ruili WEI ; Wenqian PENG ; Yuanyuan LI ; Xin CUI ; Xiaoxiao ZHAO ; Fumei LIU ; Mengmeng WANG ; Yanming XIE ; Lianxin WANG
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(8):245-251
To standardize the clinical application of oral Chinese patent medicines (CPMs), and address the safety issues arising from their dosage form characteristics, irrational clinical use, and the lack of targeted pharmacovigilance systems, the China Association of Chinese Medicine organized the formulation and release of Pharmacovigilance Guidelines for Clinical Application of Oral Chinese Patent Medicines, aiming to inform the safe clinical use of oral CPMs and related pharmacovigilance work. According to the principles of GB/T1.1—2020 and the Drug Administration Law of the People's Republic of China (2019 revision), the Institute of Basic Research in Clinical Medicine, China Academy of Chinese Medical Sciences, led a drafting group comprising 18 institutions. After multiple rounds of expert interviews, literature retrieval, evidence screening, and extensive solicitation of opinions, the Guidelines were registered internationally. Systematic standardization focused on safety monitoring, risk identification, assessment, control, and other aspects. The Guidelines clarified the characteristics of oral CPMs in terms of safety monitoring, known risks, and potential risks, compared to non-oral CPMs. Then, risk control measures were proposed, including medication in special populations and irrational medication. As a special guideline for pharmacovigilance in the clinical application of oral CPMs, the Guidelines systematically construct a technical system in line with the characteristics of traditional Chinese medicine (TCM), which is essential for improving the clinical safety management of oral CPMs and provides an important reference for medical institutions, pharmaceutical manufacturers, and regulatory authorities.
4.Compilation Instruction for Pharmacovigilance Guidelines for Clinical Application of Oral Chinese Patent Medicines
Hongyan ZHANG ; Zhifei WANG ; Shuo YANG ; Ruili WEI ; Wenqian PENG ; Yuanyuan LI ; Xin CUI ; Xiaoxiao ZHAO ; Fumei LIU ; Mengmeng WANG ; Yanming XIE ; Lianxin WANG
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(8):245-251
To standardize the clinical application of oral Chinese patent medicines (CPMs), and address the safety issues arising from their dosage form characteristics, irrational clinical use, and the lack of targeted pharmacovigilance systems, the China Association of Chinese Medicine organized the formulation and release of Pharmacovigilance Guidelines for Clinical Application of Oral Chinese Patent Medicines, aiming to inform the safe clinical use of oral CPMs and related pharmacovigilance work. According to the principles of GB/T1.1—2020 and the Drug Administration Law of the People's Republic of China (2019 revision), the Institute of Basic Research in Clinical Medicine, China Academy of Chinese Medical Sciences, led a drafting group comprising 18 institutions. After multiple rounds of expert interviews, literature retrieval, evidence screening, and extensive solicitation of opinions, the Guidelines were registered internationally. Systematic standardization focused on safety monitoring, risk identification, assessment, control, and other aspects. The Guidelines clarified the characteristics of oral CPMs in terms of safety monitoring, known risks, and potential risks, compared to non-oral CPMs. Then, risk control measures were proposed, including medication in special populations and irrational medication. As a special guideline for pharmacovigilance in the clinical application of oral CPMs, the Guidelines systematically construct a technical system in line with the characteristics of traditional Chinese medicine (TCM), which is essential for improving the clinical safety management of oral CPMs and provides an important reference for medical institutions, pharmaceutical manufacturers, and regulatory authorities.
5.Safety of using glucagon-like peptide-1 receptor agonists before gastrointestinal endoscopy:an overview of systematic reviews
Yuzhou LI ; Shuying ZOU ; Xiangnan ZHU ; Li TANG ; Peng LI ; Caixia XIE
China Pharmacy 2026;37(6):806-811
OBJECTIVE To conduct a systematic review concerning the safety of using glucagon-like peptide-1 receptor agonists (GLP-1RA) before gastrointestinal endoscopy. METHODS Chinese and English databases including CNKI, Wanfang Data, VIP, CBM, and PubMed were searched to collect systematic reviews and meta-analyses on the safety of using GLP-1RA before gastrointestinal endoscopy, with a search period from the inception to September 30, 2025. Report quality, methodological quality, risk of bias, and evidence quality were assessed using the PRISMA 2020 statement, AMSTAR 2 scale, ROBIS tool, and GRADE tool, respectively. Corrected covered area (CCA) was used to quantitatively evaluate the degree of outcome overlap, and a comprehensive quality analysis was performed on the quantitative results of systematic reviews/meta-analyses. RESULTS Ten studies were included. All 10 stu dies had some information deficiencies (15.5-19.5 points), and were at high risk of bias; 9 studies were extremely low methodological quality, while 1 study was low. In terms of evidence quality, among 88 outcome indexes, there was 1 moderate-level index, 28 low-level indexes, and 59 extremely low-level indexes. The CCA values of the incidence of residual gastric contents, aspiration, endoscopy interruption, repeated endoscopy, inadequate bowel preparation and Boston Bowel Preparation Scale scores were 37.30%, 35.00%, 35.00%, 50.00%, 29.60% and 20.00%, respectively. Results of comprehensive quality analysis showed that compared with the control group, the incidence of residual gastric contents, endoscopy interruption and repeated endoscopy were increased significantly in the intervention group, along with a notably prolonged gastric emptying time and a significantly lower score of Boston Bowel Preparation Scale ( P <0.05). However, the study results regarding the effects of GLP-1RA on the incidence of aspiration and inadequate bowel preparation were inconsistent. CONCLUSIONS The use of GLP-1RA before gastrointestinal endoscopy can increase certain safety risks, including residual gastric contents, endoscopy interruption and repeated endoscopy, prolong gastric emptying time, and reduce the quality of bowel preparation. However, the effects on aspiration and inadequate bowel preparation remain controversial. The reports included in systematic reviews/meta-analyses exhibited low quality in reporting, methodology and evidence, with high risk of bias. Therefore, conclusions should be interpreted with caution.
6.Interpretation of Pharmacovigilance Guidelines for Clinical Application of Oral Chinese Patent Medicines
Wenxi PENG ; Meng QIAO ; Lianxin WANG ; Yuanyuan LI ; Xiuhui LI ; Xin CUI ; Zijia CHEN ; Xinyi CHEN ; Yi DENG ; Yanming XIE ; Zhifei WANG
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(6):152-160
The Pharmacovigilance Guidelines for Clinical Application of Oral Chinese Patent Medicines (hereinafter referred to as the Guidelines) is first specialized in the field of drug safety for oral Chinese patent medicines (OCPMs) in China. Rooted in China's healthcare context, the Guidelines address the unique usage patterns and risk characteristics of OCPMs, filling a regulatory gap in the pharmacovigilance framework specific to this category. To facilitate accurate understanding and effective implementation of the Guidelines, and to promote the standardized development of pharmacovigilance practices for OCPMs, this study offered a systematic interpretation based on its three core components. In the domain of risk monitoring and reporting, the paper analyzed the rationale for multi-source information integration and clarified the criteria for identifying key products and target populations for intensive monitoring. Regarding risk assessment, the Guidelines were examined from three dimensions of formulation components, medication behaviors, and population to address complex safety issues arising from medicinal constituents, irrational use, and individual susceptibility. In the area of risk control, the analysis focused on context-based interventions and dynamic closed-loop management strategies, exploring practical pathways to shift from passive response to proactive risk mitigation. Furthermore, this paper evaluated the applied value of the Guidelines and identified implementation challenges, such as insufficient capacity at the primary-care level and limited digital infrastructure. In response, the study proposed optimization strategies including establishing a dynamic updating mechanism, strengthening training at the grassroots level, and incorporating artificial intelligence to enhance pharmacovigilance capacity. This interpretation aims to provide actionable insights for marketing authorization holders (including manufacturers), pharmaceutical distributors, healthcare institutions, and research organizations, ultimately supporting the establishment and refinement of a full lifecycle pharmacovigilance system for OCPMs.
7.Current quality status and management countermeasures of occupational health technical services in Zhejiang Province
Qiuliang XU ; Feng HAN ; Peng WANG ; Zhen ZHOU ; Fei LI ; Hongwei XIE ; Yong HU ; Weiming YUAN ; Lifang ZHOU ; Hua ZOU
Journal of Environmental and Occupational Medicine 2026;43(3):341-346
Background The quality of occupational health technical services is directly linked to the protection of workers' health rights and the efficacy of occupational disease prevention and control. However, the industry still faces critical challenges: sporadic instances of institutional non-compliance and persistent irregularities in professional practice continue to undermine overall service performance. Objective To assess the current quality status of occupational health technical services in Zhejiang Province and propose countermeasures for quality improvement, providing a scientific basis for policy optimization and service delivery quality enhancement. Methods A total of 69 occupational health technical service institutions in Zhejiang Province that obtained formal accreditation as of April 30, 2024, were sampled, including 3 public institutions and 66 private institutions (comprising 3 formerly Class-A, 28 formerly Class-B, 11 formerly Class-C, and 24 newly certified institutions). Following the Technical Protocol for Quality Monitoring of Occupational Health Technical Service in Zhejiang Province and the Technical Protocol for Proficiency Testing of Occupational Health Detection in Zhejiang Province, a quality assessment task force comprising national and provincial experts was established. Evaluation was conducted across four dimensions: qualification maintenance and compliance, standardization of technical services, authenticity of technical services, and proficiency testing, utilizing a combination of document review, on-site inspections, and technical skill assessments. Results The occupational health technical service institutions in Zhejiang Province were predominantly private entities (82.5%), with significant disparities in overall service quality. The pass rates for qualification maintenance and compliance, technical service standardization, technical service authenticity, and the excellence rate for laboratory proficiency testing were 81.5%, 80.7%, 97.3%, and 90.4%, respectively. Regarding qualification maintenance, the pass rates for "environmental conditions" (49.8%, 56.7%) and "instrumentation and equipment" (58.2%、65.6%) were significantly lower for formerly Class-C and newly certified institutions compared to other categories. In terms of technical standardization, "standardized on-site inspections" recorded the lowest pass rate (67.4%), with newly certified institutions at only 48.0%. Regarding technical service authenticity, formerly Class-C institutions exhibited issues such as missing raw chromatograms for blank samples (85.7% pass rate). In laboratory proficiency testing, public and formerly Class-A institutions achieved 100% excellence rates, but the performance of formerly Class-C and newly certified institutions was comparatively weak; specifically, the failure rate for organic analysis in formerly Class-C institutions reached 20%; the failure rate for dust testing items in newly certified institutions was 10.3%. Conclusion The overall quality of occupational health technical services in Zhejiang Province still requires significant improvement, particularly in basic institutional conditions, the standardization of on-site inspections, and laboratory proficiency in organic and dust analysis. Formerly Class-C and newly certified institutions should be the primary focus of quality management efforts. Differentiated regulatory strategies are recommended, alongside strengthening interim and ex-post supervision to gradually enhance the quality of occupational health technical services across all institutions.
8.Olfactory Receptors Expressed in The Intestine and Their Functions
Pei-Wen YANG ; Meng-Meng YUAN ; Ying ZHOU ; Peng LI ; Gui-Hong QI ; Ying YANG ; Zhong-Yi MAO ; Meng-Sha ZHOU ; Xiao-Shuang MAO ; Jian-Ping XIE ; Yi-Nan YANG ; Shi-Hao SUN
Progress in Biochemistry and Biophysics 2026;53(3):534-549
Olfactory receptors (ORs) form the largest superfamily of G protein-coupled receptors (GPCRs). Traditionally recognized for their role in the nasal olfactory epithelium, where they mediate the sense of smell, accumulating evidence has firmly established their ectopic expression in non-olfactory tissues, including the intestine, lungs, and kidneys. The intestine, as the primary site for nutrient digestion and absorption, harbors a highly complex chemical environment. To adapt to this environment, the gut employs a sophisticated network of “chemosensors” to monitor luminal contents and maintain homeostasis. Among these sensors, intestinal ORs have emerged as crucial functional components, serving as a molecular bridge that connects environmental chemical signals—such as food-derived odorants—to specific physiological responses. This discovery has significantly deepened our understanding of how dietary flavors and compounds influence intestinal physiology at the molecular level. This review systematically summarizes the expression profiles, ligand classification, and biological functions of ORs within the gastrointestinal tract. Studies indicate that intestinal ORs exhibit distinct spatial distribution patterns across different gut segments and display cell-type specificity, particularly within enterocytes and enteroendocrine cells. These receptors function as versatile sensors capable of recognizing a wide variety of ligands, including exogenous dietary components, gut microbiota metabolites such as short-chain fatty acids, and endogenous small molecules like azelaic acid. Upon activation by specific ligands, intestinal ORs trigger intracellular signaling cascades, primarily involving the AC-cAMP-PKA pathway or calcium influx channels. A major focus of this review is to elucidate the molecular mechanisms by which these receptors regulate the secretion of gut hormones. Activation of specific ORs in enteroendocrine cells has been shown to stimulate the release of hormones such as glucagon-like peptide-1 (GLP-1), peptide YY (PYY), and serotonin (5-HT), thereby modulating systemic energy metabolism, glucose homeostasis, and gastrointestinal motility. Furthermore, the review addresses the critical roles of ORs in immune regulation and pathology. Evidence suggests that specific ORs contribute to the maintenance of intestinal immune homeostasis and may offer protection against inflammation. Beyond their involvement in inflammatory responses, ORs such as Olfr78 have been shown to regulate the differentiation and function of intestinal endocrine cells. Similarly, Olfr544 has been demonstrated to alleviate intestinal inflammation by remodeling the gut microbiome and metabolome. These findings collectively suggest that specific ORs hold promise as therapeutic targets for mitigating intestinal inflammation and maintaining gut homeostasis. Additionally, the review explores the emerging role of ORs in cancer. Although OR expression is often downregulated in tumor tissues compared to normal mucosa, activation of specific ORs by certain ligands can inhibit tumor cell proliferation and migration and induce apoptosis via pathways such as MEK/ERK and p38 MAPK. Conversely, other receptors, such as OR7C1, may serve as biomarkers for cancer-initiating cells. In conclusion, intestinal ORs represent a vital component of the gut’s sensory network. The review also discusses the translational potential of these findings. By elucidating the precise pairing relationships between dietary components and specific ORs, novel therapeutic strategies could be developed. Intestinal ORs may thus emerge as promising targets for nutritional and pharmacological interventions in metabolic diseases, inflammatory bowel diseases, and malignancies.
9.The Diversity of Filamentous Morphologies and Magnetic Sensitivity Modulated by Diverse MagR Expression in Bacteria
Ya-Fei CHANG ; Jing ZHANG ; Peng ZHANG ; Xiu-Juan ZHOU ; Meng-Ke WEI ; Tian-Tian CAI ; Pei-Qi HE ; Jun-Feng WANG ; Can XIE
Progress in Biochemistry and Biophysics 2026;53(5):1439-1456
Objective Magnetoreception, the remarkable ability of diverse animals to sense and utilize the geomagnetic field for orientation and navigation, remains a molecularly unresolved mystery in sensory biology. The putative magnetoreceptor (MagR, previously known as IscA1) is a highly conserved iron-sulfur protein implicated in both magnetoreception and iron metabolism; however, the functional diversity among its cross-species homologs remains poorly understood. Cellular morphology is a key genetically determined trait that can be altered through genetic or environmental modifications—a process known as cell morphology engineering. Constructing engineered cells with specific morphological features and magnetic sensitivity to achieve remote, non-invasive magnetic modulation represents a crucial goal in this field with significant application potential. Therefore, this study aims to systematically investigate the effects of MagR heterologous expression on bacterial morphology and magnetic sensing capabilities, screen for MagR-based magnetically sensitive morphology engineering pathways, and reveal the underlying molecular mechanisms. Methods We systematically screened 28 MagR homologous genes from diverse prokaryotic and animal taxa to evaluate their expression and corresponding phenotypic effects in Escherichia coli (E. coli). To compare the differential magnetic responses among bacteria expressing various recombinant MagR proteins, we utilized high-throughput automated bright-field microscopic imaging and scanning electron microscopy (SEM). Furthermore, comprehensive biochemical and biophysical characterizations of iron and iron-sulfur cluster binding were performed using Ferrozine colorimetric assays, electron paramagnetic resonance (EPR) spectroscopy, ultraviolet-visible (UV-Vis) absorption, and circular dichroism (CD) spectroscopy. Additionally, 100 mT static magnetic field (SMF) exposure experiments were conducted to assess magnetically tunable phenotypes, while the intrinsic magnetic properties of purified MagR proteins were directly measured using a superconducting quantum interference device (SQUID) magnetometer. Results Our results demonstrated that the heterologous expression of MagR homologs induced varying degrees of bacterial filamentation. From this comprehensive screen, two distinct morphological patterns were identified: hydra (Hydra vulgaris) MagR (hyMagR) promoted uniform cell elongation and filamentation, exhibiting robust magnetic sensitivity manifested as significantly enhanced filamentation under the 100 mT SMF. In contrast, pigeon (Columba livia) MagR (clMagR) induced only low-frequency, extreme filamentation (sporadically exceeding 80 μm) with a relatively weaker magnetic morphological response. Mechanistically, our data unambiguously proved that these phenotypic differences are primarily driven by distinct iron redox preferences rather than total cellular iron accumulation. Specifically, hyMagR preferentially binds ferrous iron (Fe2+), whereas clMagR favors ferric iron (Fe3+) and forms more stable iron-sulfur clusters. Intriguingly, although SQUID magnetometry showed that purified clMagR exhibited approximately five-fold higher mass magnetic susceptibility than hyMagR, its cellular magnetic response was weaker. We hypothesize that the Fe2+-preferred intracellular environment associated with hyMagR overexpression primes the cell for enhanced generation of reactive oxygen species (ROS) via the Fenton reaction. Exposure to an SMF synergizes with this primed redox state, triggering the bacterial SOS response and upregulating cell division inhibitors to efficiently induce uniform filamentation. Conclusion Our findings identify the Fe2+/Fe3+ redox state as a critical determinant of MagR-mediated morphological remodeling and magnetic responsiveness. This discovery suggests a potential strategy for engineering magnetically responsive cellular systems for synthetic biology applications, and provides a plausible framework, which potentially combines intrinsic protein magnetism with redox-state modulation, for further investigating the evolutionary mechanisms of MagR-mediated magnetoreception.
10.The Diversity of Filamentous Morphologies and Magnetic Sensitivity Modulated by Diverse MagR Expression in Bacteria
Ya-Fei CHANG ; Jing ZHANG ; Peng ZHANG ; Xiu-Juan ZHOU ; Meng-Ke WEI ; Tian-Tian CAI ; Pei-Qi HE ; Jun-Feng WANG ; Can XIE
Progress in Biochemistry and Biophysics 2026;53(5):1439-1456
Objective Magnetoreception, the remarkable ability of diverse animals to sense and utilize the geomagnetic field for orientation and navigation, remains a molecularly unresolved mystery in sensory biology. The putative magnetoreceptor (MagR, previously known as IscA1) is a highly conserved iron-sulfur protein implicated in both magnetoreception and iron metabolism; however, the functional diversity among its cross-species homologs remains poorly understood. Cellular morphology is a key genetically determined trait that can be altered through genetic or environmental modifications—a process known as cell morphology engineering. Constructing engineered cells with specific morphological features and magnetic sensitivity to achieve remote, non-invasive magnetic modulation represents a crucial goal in this field with significant application potential. Therefore, this study aims to systematically investigate the effects of MagR heterologous expression on bacterial morphology and magnetic sensing capabilities, screen for MagR-based magnetically sensitive morphology engineering pathways, and reveal the underlying molecular mechanisms. Methods We systematically screened 28 MagR homologous genes from diverse prokaryotic and animal taxa to evaluate their expression and corresponding phenotypic effects in Escherichia coli (E. coli). To compare the differential magnetic responses among bacteria expressing various recombinant MagR proteins, we utilized high-throughput automated bright-field microscopic imaging and scanning electron microscopy (SEM). Furthermore, comprehensive biochemical and biophysical characterizations of iron and iron-sulfur cluster binding were performed using Ferrozine colorimetric assays, electron paramagnetic resonance (EPR) spectroscopy, ultraviolet-visible (UV-Vis) absorption, and circular dichroism (CD) spectroscopy. Additionally, 100 mT static magnetic field (SMF) exposure experiments were conducted to assess magnetically tunable phenotypes, while the intrinsic magnetic properties of purified MagR proteins were directly measured using a superconducting quantum interference device (SQUID) magnetometer. Results Our results demonstrated that the heterologous expression of MagR homologs induced varying degrees of bacterial filamentation. From this comprehensive screen, two distinct morphological patterns were identified: hydra (Hydra vulgaris) MagR (hyMagR) promoted uniform cell elongation and filamentation, exhibiting robust magnetic sensitivity manifested as significantly enhanced filamentation under the 100 mT SMF. In contrast, pigeon (Columba livia) MagR (clMagR) induced only low-frequency, extreme filamentation (sporadically exceeding 80 μm) with a relatively weaker magnetic morphological response. Mechanistically, our data unambiguously proved that these phenotypic differences are primarily driven by distinct iron redox preferences rather than total cellular iron accumulation. Specifically, hyMagR preferentially binds ferrous iron (Fe2+), whereas clMagR favors ferric iron (Fe3+) and forms more stable iron-sulfur clusters. Intriguingly, although SQUID magnetometry showed that purified clMagR exhibited approximately five-fold higher mass magnetic susceptibility than hyMagR, its cellular magnetic response was weaker. We hypothesize that the Fe2+-preferred intracellular environment associated with hyMagR overexpression primes the cell for enhanced generation of reactive oxygen species (ROS) via the Fenton reaction. Exposure to an SMF synergizes with this primed redox state, triggering the bacterial SOS response and upregulating cell division inhibitors to efficiently induce uniform filamentation. Conclusion Our findings identify the Fe2+/Fe3+ redox state as a critical determinant of MagR-mediated morphological remodeling and magnetic responsiveness. This discovery suggests a potential strategy for engineering magnetically responsive cellular systems for synthetic biology applications, and provides a plausible framework, which potentially combines intrinsic protein magnetism with redox-state modulation, for further investigating the evolutionary mechanisms of MagR-mediated magnetoreception.

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