Iron-Sulfur Proteins

铁硫蛋白
  • 文章类型: Journal Article
    在目前的研究中,我们旨在研究双硫仑(DSF)是否通过调节铁氧还蛋白1(FDX1)调节铜离子(Cu)水平和抑制炎症反应,在脑缺血再灌注(CI-RI)损伤中发挥神经保护作用.要模拟CI-RI,采用C57/BL6小鼠的短暂性大脑中动脉闭塞(tMCAO)模型。在tMCAO之前和之后,在有或没有DSF的情况下施用小鼠。使用TTC染色观察tMCAO后梗死体积的变化。采用Nissl染色和苏木精-伊红(HE)染色在显微水平上观察神经细胞的形态学变化。通过TUNEL法验证DSF对初始炎症的抑制作用,凋亡相关蛋白检测和铁浓度检测。FDX1是铜逝世亡的主要调控卵白,而铜逝世亡的发生会招致HSP70应激和炎症反响的加重。蛋白质印迹法检测细胞凋亡相关蛋白和下游炎症因子,免疫荧光染色,和免疫组织化学。使用特定的试剂盒检测铜离子的含量,而电子显微镜用于检查线粒体变化。我们发现DSF减少了脑梗死的体积,调节角化相关蛋白的表达,并通过下调FDX1的表达来调节铜含量。此外,DSF抑制HSP70/TLR-4/NLRP3信号通路。总的来说,DSF可以通过抑制FDX1调节Cu稳态,作用于HSP70/TLR4/NLRP3通路以减轻CI/RI。因此,DSF可以减轻炎症反应并保护线粒体完整性,为缺血再灌注损伤的临床治疗提供新的治疗靶点和机制。
    In the current study, we aimed to investigate whether disulfiram (DSF) exerts a neuroprotective role in cerebral ischemiareperfusion (CI-RI) injury by modulating ferredoxin 1 (FDX1) to regulate copper ion (Cu) levels and inhibiting inflammatory responses. To simulate CI-RI, a transient middle cerebral artery occlusion (tMCAO) model in C57/BL6 mice was employed. Mice were administered with or without DSF before and after tMCAO. Changes in infarct volume after tMCAO were observed using TTC staining. Nissl staining and hematoxylin-eosin (he) staining were used to observe the morphological changes of nerve cells at the microscopic level. The inhibitory effect of DSF on initial inflammation was verified by TUNEL assay, apoptosis-related protein detection and iron concentration detection. FDX1 is the main regulatory protein of copper death, and the occurrence of copper death will lead to the increase of HSP70 stress and inflammatory response. Cuproptosis-related proteins and downstream inflammatory factors were detected by western blotting, immunofluorescence staining, and immunohistochemistry. The content of copper ions was detected using a specific kit, while electron microscopy was employed to examine mitochondrial changes. We found that DSF reduced the cerebral infarction volume, regulated the expression of cuproptosis-related proteins, and modulated copper content through down regulation of FDX1 expression. Moreover, DSF inhibited the HSP70/TLR-4/NLRP3 signaling pathway. Collectively, DSF could regulate Cu homeostasis by inhibiting FDX1, acting on the HSP70/TLR4/NLRP3 pathway to alleviate CI/RI. Accordingly, DSF could mitigate inflammatory responses and safeguard mitochondrial integrity, yielding novel therapeutic targets and mechanisms for the clinical management of ischemia-reperfusion injury.
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  • 文章类型: Journal Article
    基因组维持和复制所必需的细胞质和核铁-硫(Fe-S)酶取决于用于簇获取的细胞质Fe-S组装(CIA)机制。CIA机械的核心由CIAO1,MMS19和FAM96B的复合物组成。迄今为止,CIA途径组分功能丧失的生理后果仍未表征。我们的研究表明,在CIAO1中,双等位基因功能丧失的患者出现了近端和轴向肌无力,波动的肌酸激酶升高,和呼吸功能不全。此外,他们出现中枢神经系统症状,包括学习困难和神经行为合并症,随着铁沉积在大脑深部核中,轻度正常细胞性到大细胞性贫血,和胃肠道症状。突变分析显示与WTCIAO1相比,变体的稳定性降低。功能测定表明在患者中鉴定的变体未能招募Fe-S受体蛋白,导致DNA解旋酶的活性受损,聚合酶,并修复依赖CIA复合物获得Fe-S辅因子的酶。慢病毒介导的CIAO1表达恢复逆转了所有患者衍生的细胞异常。我们的研究将CIAO1鉴定为人类疾病基因,并提供了对细胞溶质Fe-S组装途径在人类健康和疾病中的更广泛意义的见解。
    Cytoplasmic and nuclear iron-sulfur (Fe-S) enzymes that are essential for genome maintenance and replication depend on the cytoplasmic Fe-S assembly (CIA) machinery for cluster acquisition. The core of the CIA machinery consists of a complex of CIAO1, MMS19 and FAM96B. The physiological consequences of loss of function in the components of the CIA pathway have thus far remained uncharacterized. Our study revealed that patients with biallelic loss of function in CIAO1 developed proximal and axial muscle weakness, fluctuating creatine kinase elevation, and respiratory insufficiency. In addition, they presented with CNS symptoms including learning difficulties and neurobehavioral comorbidities, along with iron deposition in deep brain nuclei, mild normocytic to macrocytic anemia, and gastrointestinal symptoms. Mutational analysis revealed reduced stability of the variants compared with WT CIAO1. Functional assays demonstrated failure of the variants identified in patients to recruit Fe-S recipient proteins, resulting in compromised activities of DNA helicases, polymerases, and repair enzymes that rely on the CIA complex to acquire their Fe-S cofactors. Lentivirus-mediated restoration of CIAO1 expression reversed all patient-derived cellular abnormalities. Our study identifies CIAO1 as a human disease gene and provides insights into the broader implications of the cytosolic Fe-S assembly pathway in human health and disease.
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  • 文章类型: English Abstract
    目的:探讨3例晚发型多酰基辅酶A脱氢酶缺乏症(MADDⅢ型)患儿的临床特点及遗传变异。
    方法:回顾性分析2020年3月至2022年3月郑州大学附属儿童医院收治的3例晚发性MADD患儿的临床资料。所有儿童均接受全外显子组测序(WES),和候选变体通过Sanger测序进行验证。所有患儿均接受改善代谢治疗,随访1~3年。
    结果:儿童包括2名男性和1名女性,年龄由2个月至11岁零7个月。儿童1有间歇性呕吐,孩子2有下肢无力,而儿童3除了异常新生儿筛查外没有任何症状。三个孩子的串联质谱显示多个酰基肉碱升高,中链和长链。儿童1和2通过尿液气相色谱-质谱(GC-MS)分析显示戊二酸和多种二羧酸增加。发现所有儿童都带有ETFDH基因的复合杂合变体,包括父系c.1211T>C(p。M404T)和儿童1的母体c.488-22T>G变体,父系c.1717C>T(p。Q573X)和母体c.250G>A(p。A84T)在儿童2中变异,父系c.12851G>A,母系c.629A>G(p。S210N)子3中的变体。至于治疗,给予大剂量维生素B2、左卡尼汀和辅酶Q10以改善代谢,除了低脂肪,低蛋白质和高碳水化合物饮食。所有患儿在随访期间病情稳定,生长发育正常。
    结论:ETFDH基因的复合杂合变体可能是肌肉无力的基础,及时呕吐,升高短,中等,和长链酰基肉碱,3例Ⅲ型MADD患儿戊二酸和各种二羧酸水平升高。
    OBJECTIVE: To explore the clinical characteristics and genetic variants in three children with late-onset Multiple acyl-Coenzyme A dehydrogenase deficiency (MADD type Ⅲ).
    METHODS: Clinical data of three children diagnosed with late-onset MADD at the Children\'s Hospital Affiliated to Zhengzhou University between March 2020 and March 2022 were retrospectively analyzed. All children were subjected to whole exome sequencing (WES), and candidate variants were verified by Sanger sequencing. All children had received improved metabolic therapy and followed up for 1 ~ 3 years.
    RESULTS: The children had included 2 males and 1 female, and aged from 2 months to 11 years and 7 months. Child 1 had intermittent vomiting, child 2 had weakness in lower limbs, while child 3 had no symptom except abnormal neonatal screening. Tandem mass spectrometry of the three children showed elevation of multiple acylcarnitines with short, medium and long chains. Children 1 and 2 showed increased glutaric acid and multiple dicarboxylic acids by urine Gas chromatography-mass spectrometry (GC-MS) analysis. All children were found to harbor compound heterozygous variants of the ETFDH gene, including a paternal c.1211T>C (p.M404T) and a maternal c.488-22T>G variant in child 1, a paternal c.1717C>T (p.Q573X) and a maternal c.250G>A (p.A84T) variant in child 2, and a paternal c.1285+1G>A and maternal c.629A>G (p.S210N) variant in child 3. As for the treatment, high-dose vitamin B2, levocarnitine and coenzyme Q10 were given to improve the metabolism, in addition with a low fat, hypoproteinic and high carbohydrate diet. All children showed a stable condition with normal growth and development during the follow-up.
    CONCLUSIONS: The compound heterozygous variants of the ETFDH gene probably underlay the muscle weakness, remittent vomiting, elevated short, medium, and long chain acylcarnitine, as well as elevated glutaric acid and various dicarboxylic acids in the three children with type Ⅲ MADD.
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  • 文章类型: Journal Article
    烟曲霉是人类的主要霉菌病原体。先前已证明适应宿主施加的铁限制对其毒力至关重要。[2Fe-2S]簇作为几种代谢途径的辅因子是至关重要的,并且在真菌(包括烟曲霉)中介导胞质/核铁传感。[2Fe-2S]簇运输已被证明涉及线粒体和细胞质/细胞核中的BolA家族蛋白。有趣的是,两个烟曲霉同源物,称为Bol1和Bol3,具有线粒体靶向序列,表明缺乏细胞溶质/核版本。这里,我们通过突变的组合来显示,蛋白质组学和荧光显微镜分析,Bol3编码基因的表达导致基因产物通过线粒体靶向序列下游的替代翻译起始到线粒体和细胞质/细胞核的双重定位,在各种曲霉属物种中似乎高度保守。线粒体Bol1或Bol3的缺乏在表型上并不明显,而在铁限制期间,胞质/核Bol3的缺乏会损害生长,但不是铁感应,这表明[2Fe-2S]簇运输在铁限制期间特别重要。值得注意的是,胞质/核Bol3与线粒体版本的不同之处仅在于N端乙酰化,这一发现只有通过突变假设检验才有可能。
    Aspergillus fumigatus is the predominant mould pathogen for humans. Adaption to host-imposed iron limitation has previously been demonstrated to be essential for its virulence. [2Fe-2S] clusters are crucial as cofactors of several metabolic pathways and mediate cytosolic/nuclear iron sensing in fungi including A. fumigatus. [2Fe-2S] cluster trafficking has been shown to involve BolA family proteins in both mitochondria and the cytosol/nucleus. Interestingly, both A. fumigatus homologues, termed Bol1 and Bol3, possess mitochondrial targeting sequences, suggesting the lack of cytosolic/nuclear versions. Here, we show by the combination of mutational, proteomic and fluorescence microscopic analyses that expression of the Bol3 encoding gene leads to dual localization of gene products to mitochondria and the cytosol/nucleus via alternative translation initiation downstream of the mitochondrial targeting sequence, which appears to be highly conserved in various Aspergillus species. Lack of either mitochondrial Bol1 or Bol3 was phenotypically inconspicuous while lack of cytosolic/nuclear Bol3 impaired growth during iron limitation but not iron sensing which indicates a particular importance of [2Fe-2S] cluster trafficking during iron limitation. Remarkably, cytosolic/nuclear Bol3 differs from the mitochondrial version only by N-terminal acetylation, a finding that was only possible by mutational hypothesis testing.
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  • 文章类型: Journal Article
    甲基赤藓糖醇磷酸酯(MEP)途径负责真细菌和质体中类异戊二烯化合物前体的生物合成。它是在古细菌和真核生物中发现的用于类异戊二烯生产的众所周知的甲羟戊酸途径的代谢替代品。最近,MEP途径在氧化应激检测中的作用,信令,反应已经确定。此角色部分通过不寻常的循环中间执行,甲基赤藓糖醇环二磷酸(MEcDP)。我们推测,这种反应是通过MEP途径的末端铁-硫(Fe-S)簇酶的氧敏感性触发的。MEcDP是IspG的底物,途径中的第一个Fe-S簇酶;它在氧化应激条件下积累并充当信号分子。它也可以作为抗氧化剂。此外,有证据表明,MEP途径在氧化应激反应中具有更广泛和高度细微的作用,通过在路径中的许多节点处的不同调节和灵敏度的复杂系统来实现。这里,我们探索了这种作用的证据(包括Fe-S簇酶和不同途径代谢物的贡献,尤其是MEcDP),进化的含义,以及在存在氧化应激的情况下MEP途径的行为仍存在许多问题。
    The methylerythritol phosphate (MEP) pathway is responsible for biosynthesis of the precursors of isoprenoid compounds in eubacteria and plastids. It is a metabolic alternative to the well-known mevalonate pathway for isoprenoid production found in archaea and eukaryotes. Recently, a role for the MEP pathway in oxidative stress detection, signalling, and response has been identified. This role is executed in part through the unusual cyclic intermediate, methylerythritol cyclodiphosphate (MEcDP). We postulate that this response is triggered through the oxygen sensitivity of the MEP pathway\'s terminal iron-sulfur (Fe-S) cluster enzymes. MEcDP is the substrate of IspG, the first Fe-S cluster enzyme in the pathway; it accumulates under oxidative stress conditions and acts as a signalling molecule. It may also act as an antioxidant. Furthermore, evidence is emerging for a broader and highly nuanced role of the MEP pathway in oxidative stress responses, implemented through a complex system of differential regulation and sensitivity at numerous nodes in the pathway. Here, we explore the evidence for such a role (including the contribution of the Fe-S cluster enzymes and different pathway metabolites, especially MEcDP), the evolutionary implications, and the many questions remaining about the behaviour of the MEP pathway in the presence of oxidative stress.
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  • 文章类型: Journal Article
    Magnetic sense, or termed magnetoreception, has evolved in a broad range of taxa within the animal kingdom to facilitate orientation and navigation. MagRs, highly conserved A-type iron-sulfur proteins, are widely distributed across all phyla and play essential roles in both magnetoreception and iron-sulfur cluster biogenesis. However, the evolutionary origins and functional diversification of MagRs from their prokaryotic ancestor remain unclear. In this study, MagR sequences from 131 species, ranging from bacteria to humans, were selected for analysis, with 23 representative sequences covering species from prokaryotes to Mollusca, Arthropoda, Osteichthyes, Reptilia, Aves, and mammals chosen for protein expression and purification. Biochemical studies revealed a gradual increase in total iron content in MagRs during evolution. Three types of MagRs were identified, each with distinct iron and/or iron-sulfur cluster binding capacity and protein stability, indicating continuous expansion of the functional roles of MagRs during speciation and evolution. This evolutionary biochemical study provides valuable insights into how evolution shapes the physical and chemical properties of biological molecules such as MagRs and how these properties influence the evolutionary trajectories of MagRs.
    地球上的许多动物在漫长的演化过程中发展出利用微弱的地磁场进行精确定向和导航的能力,被称为磁感觉或磁感应。动物磁感应中的关键蛋白,磁受体MagR是一种高度保守的A型铁硫蛋白,曾命名为铁硫簇合成蛋白1(IscA1)。MagR广泛分布于所有生物门类,在磁感应和铁硫簇的生物合成过程中都发挥着重要作用。然而,目前关于MagR是如何从其原核祖先演化而来并在不同物种中被赋予多种功能尚不清楚。该研究对来自细菌到人类的131个物种的MagR序列进行比对分析,并选择了从原核生物到软体动物、节肢动物、骨鱼动物、爬行动物、鸟类和哺乳类动物中的23个具有代表性的物种的MagR序列进行蛋白质表达和纯化。进一步的生化研究表明,MagR中的总铁含量在演化过程中逐渐增加。根据不同物种中MagR的铁和铁硫簇的结合特征,可将其分为三种类型,且结果显示MagR的铁硫簇结合是在真核生物的演化中出现,铁硫簇结合能力在演化中逐渐上升,稳定性也逐渐提高。这也显示了MagR的功能随着物种演化的进行不断得到增强和扩展的进程。该文通过生物演化分析与生物化学研究的整合,揭示了生物分子如MagR是如何在演化过程中被赋予特殊的物理和化学特性,而这些特性又是如何反过来影响其功能的分子演化历程。.
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  • 文章类型: Journal Article
    微生物氢(H2)循环是各种缺氧生态系统的多样性和功能性的基础。在负责的三个进化上不同的氢化酶超家族中,[FeFe]氢化酶被认为仅限于细菌和真核生物。这里,我们证明厌氧古细菌编码多种,活跃,通过将现有和新基因组的分析与广泛的生化实验相结合,以及[FeFe]氢化酶的古老谱系。[FeFe]氢化酶由9个古细菌门的基因组编码,并由产生H2的Asgard古细菌培养物表达。我们报告了DPANN古细菌中的超氨基氢化酶,该酶结合催化H簇并产生H2。此外,我们鉴定并表征了通过[FeFe]和[NiFe]氢化酶在其他十个古细菌中融合形成的显着杂合复合物。系统发育分析和结构模型表明,混合氢化酶具有深刻的进化史。这些发现揭示了古细菌的新代谢适应,用于生物技术开发的流线型H2催化剂,以及两种主要的H2代谢酶之间令人惊讶地交织在一起的进化史。
    Microbial hydrogen (H2) cycling underpins the diversity and functionality of diverse anoxic ecosystems. Among the three evolutionarily distinct hydrogenase superfamilies responsible, [FeFe] hydrogenases were thought to be restricted to bacteria and eukaryotes. Here, we show that anaerobic archaea encode diverse, active, and ancient lineages of [FeFe] hydrogenases through combining analysis of existing and new genomes with extensive biochemical experiments. [FeFe] hydrogenases are encoded by genomes of nine archaeal phyla and expressed by H2-producing Asgard archaeon cultures. We report an ultraminimal hydrogenase in DPANN archaea that binds the catalytic H-cluster and produces H2. Moreover, we identify and characterize remarkable hybrid complexes formed through the fusion of [FeFe] and [NiFe] hydrogenases in ten other archaeal orders. Phylogenetic analysis and structural modeling suggest a deep evolutionary history of hybrid hydrogenases. These findings reveal new metabolic adaptations of archaea, streamlined H2 catalysts for biotechnological development, and a surprisingly intertwined evolutionary history between the two major H2-metabolizing enzymes.
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  • 文章类型: Journal Article
    兼性厌氧革兰氏阳性细菌屎肠球菌是人类肠道微生物群中普遍存在的成员。然而,它已逐渐演变成引起医院感染的致病性和多药耐药谱系。肠球菌建立高水平的肠道定植是感染的关键步骤。目前对肠球菌的研究大多是在有氧条件下进行的,尽管对其在厌氧环境中的生理特性给予了有限的关注,这反映了它在肠道中的自然定殖生态位。在这项研究中,构建了含有26,620个不同插入位点的高密度转座子突变文库。Tn-seq分析鉴定了在厌氧条件下显着促进生长的六个基因。在厌氧条件下,与有氧条件相比,sufB(编码Fe-S簇组装蛋白B)的缺失会导致碳水化合物代谢受到更广泛和显着的损害。始终如一,在厌氧条件下,与野生型相比,突变体中这种限制利用的碳水化合物所涉及的途径的表达水平明显较低。此外,sufB或pflA(编码丙酮酸甲酸裂解酶激活蛋白A)的缺失导致小鼠胃肠道定植失败。这些发现有助于我们理解屎肠球菌在厌氧条件下维持增殖并在肠道中建立定植的机制。
    The facultative anaerobic Gram-positive bacterium Enterococcus faecium is a ubiquitous member of the human gut microbiota. However, it has gradually evolved into a pathogenic and multidrug resistant lineage that causes nosocomial infections. The establishment of high-level intestinal colonization by enterococci represents a critical step of infection. The majority of current research on Enterococcus has been conducted under aerobic conditions, while limited attention has been given to its physiological characteristics in anaerobic environments, which reflects its natural colonization niche in the gut. In this study, a high-density transposon mutant library containing 26,620 distinct insertion sites was constructed. Tn-seq analysis identified six genes that significantly contribute to growth under anaerobic conditions. Under anaerobic conditions, deletion of sufB (encoding Fe-S cluster assembly protein B) results in more extensive and significant impairments on carbohydrate metabolism compared to aerobic conditions. Consistently, the pathways involved in this utilization-restricted carbohydrates were mostly expressed at significantly lower levels in mutant compared to wild-type under anaerobic conditions. Moreover, deletion of sufB or pflA (encoding pyruvate formate lyase-activating protein A) led to failure of gastrointestinal colonization in mice. These findings contribute to our understanding of the mechanisms by which E. faecium maintains proliferation under anaerobic conditions and establishes colonization in the gut.
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  • 文章类型: Journal Article
    人AAA-ATPaseBcs1L将完全组装的Rieske铁硫蛋白(ISP)前体转运穿过线粒体内膜,使呼吸复合体III组装。折叠的底物到底是如何与Bcs1L结合和释放的,目前还不清楚,关于Bcs1L的亚基在移动蛋白质货物时是否顺序或一致水解ATP,一直存在争议。这里,在存在或不存在ISP底物的情况下,我们在活性ATP水解过程中通过cryo-EM捕获了Bcs1L构象。与AAA蛋白在底物易位中广泛使用的穿线机制相反,Bcs1L的亚基在ATP和ADP构象之间均匀交替,没有可检测的中间体,共存的核苷酸状态,表明子单元一致行动。我们进一步表明,当ISP的亚基都处于ADP结合状态时,ISP可以被Bcs1捕获,我们建议以apo形式发布。
    The human AAA-ATPase Bcs1L translocates the fully assembled Rieske iron-sulfur protein (ISP) precursor across the mitochondrial inner membrane, enabling respiratory Complex III assembly. Exactly how the folded substrate is bound to and released from Bcs1L has been unclear, and there has been ongoing debate as to whether subunits of Bcs1L act in sequence or in unison hydrolyzing ATP when moving the protein cargo. Here, we captured Bcs1L conformations by cryo-EM during active ATP hydrolysis in the presence or absence of ISP substrate. In contrast to the threading mechanism widely employed by AAA proteins in substrate translocation, subunits of Bcs1L alternate uniformly between ATP and ADP conformations without detectable intermediates that have different, co-existing nucleotide states, indicating that the subunits act in concert. We further show that the ISP can be trapped by Bcs1 when its subunits are all in the ADP-bound state, which we propose to be released in the apo form.
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  • 文章类型: Journal Article
    细胞器是分隔生化和分子功能的膜结合结构。随着分子的改进,生化和显微镜工具protistan细胞器的多样性和功能近年来有所增加,提供复杂的结构/功能关系。这在氢的描述中尤其明显,以及随之而来的各种结构,具有杂合氢体/线粒体属性。这些不同的细胞器已经失去了专业,有一次,线粒体的确定成分(三羧酸循环酶和细胞色素),然而,它们都包含了组装Fe-S团簇的机器,这是他们共享的单一统一特征。细胞器的可塑性,像线粒体一样,因此,从其失去作为有氧能量产生发电厂的身份的能力中可以明显看出,同时保留了需氧菌和厌氧菌共同的关键祖先功能。有趣的是注意到Apicoplast,一种非光合质体,存在于所有根尖丛原生动物中,除了隐孢子虫和可能的gregarines,也是Fe-S簇组装蛋白的位点。事实证明,在隐孢子虫中,参与Fe-S簇生物合成的蛋白质位于线粒体残余细胞器中,称为有丝分裂体。因此,不同的生物体以不同的方式解决了包装一系列需要生命的反应的相同问题,使用不同的祖先细胞器,丢弃不需要的东西,保留必要的东西。不要以细胞器的封面来判断它,更多的是它所做的事情,永远为惊喜做好准备。
    Organelles are membrane bound structures that compartmentalize biochemical and molecular functions. With improved molecular, biochemical and microscopy tools the diversity and function of protistan organelles has increased in recent years, providing a complex panoply of structure/function relationships. This is particularly noticeable with the description of hydrogenosomes, and the diverse array of structures that followed, having hybrid hydrogenosome/mitochondria attributes. These diverse organelles have lost the major, at one time, definitive components of the mitochondrion (tricarboxylic cycle enzymes and cytochromes), however they all contain the machinery for the assembly of Fe-S clusters, which is the single unifying feature they share. The plasticity of organelles, like the mitochondrion, is therefore evident from its ability to lose its identity as an aerobic energy generating powerhouse while retaining key ancestral functions common to both aerobes and anaerobes. It is interesting to note that the apicoplast, a non-photosynthetic plastid that is present in all apicomplexan protozoa, apart from Cryptosporidium and possibly the gregarines, is also the site of Fe-S cluster assembly proteins. It turns out that in Cryptosporidium proteins involved in Fe-S cluster biosynthesis are localized in the mitochondrial remnant organelle termed the mitosome. Hence, different organisms have solved the same problem of packaging a life-requiring set of reactions in different ways, using different ancestral organelles, discarding what is not needed and keeping what is essential. Don\'t judge an organelle by its cover, more by the things it does, and always be prepared for surprises.
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