Mitochondrial genome of the dimorphic zygomycete Mucor racemosus

Mitochondria were isolated from the dimorphic zygomycete Mucor racemosus by differential centrifugation. DNA from the organelles was purified by cesium chloride-ethidium bromide isopycnic centrifugation. Examination of the mitochondrial DNA by electron microscopy revealed a circular chromosome approximately 63.8 kbp in circumference. The chromosome was digested with restriction endonucleases and the resulting DNA fragments were separated by agarose-gel electrophoresis. Electrophoretic mobilities and stoichiometry of the fragments indicated a mixed population of mtDNA molecules each with a size of about 63.4 kbp. Physical maps were constructed from analyses of fragments generated in single and double restriction digests and from the hybridization of fragments to probes for the large and small mitochondrial rRNA genes from Saccharomyces cerevisiae. The Mucor mitochondrial chromosome was found to exist in the form of two flip-flop isomers with inverted repeat sequences encoding both rRNA genes.     

A novel fungal prenyl diphosphate synthase in the dimorphic zygomycete Mucor circinelloides

Two Mucor circinelloides structural genes involved in isoprenoid biosynthesis were isolated and characterised. The isoA gene encodes a typical eukaryotic farnesyl diphosphate synthase (EC 2.5.1.10), whereas the isoB gene deduced amino acid sequence shows similarity to fungal medium-chain prenyl diphosphate synthases. By functional complementation in Escherichia coli, the isoB gene product was shown to be a solanesyl diphosphate synthase (EC 2.5.1.11), which is the first fungal enzyme reported having this specificity. In addition, a M. circinelloides one-marker-per-chromosome map was completed by contour-clamped homogeneous electric field localisation of isoA, isoB and three other isoprenoid biosynthesis genes to individual chromosomes.Abbreviations FPP farnesyl diphosphate (or pyrophosphate) - GGPP geranylgeranyl diphosphate - PrenylPP prenyl diphosphate - DPP decaprenyl diphosphate - HPP hexaprenyl diphosphate - SPP solanesyl diphosphate     

Microbial hydroxylation of cinobufagin by Mucor spinosus

Mucor spinosus has been employed for the biotransformation of cinobufagin (1) to afford three metabolites. On the basis of their physico-chemical data, the structures of the transformation products have been characterized as 1β-hydroxy-cinobufagin (2), 12β-hydroxy-cinobufagin (3) and 1β,12β-dihydroxy-cinobufagin (4), of which metabolites 2 and 4 are new compounds. In vitro cytotoxic activities of the biotransformation products and the substrate-cinobufagin have been assayed against four tumor cell lines of Bel 7420, BGC 823, HeLa and HL 60; they all showed cytotoxic activities.     

胃及十二指肠溃疡伴毛霉菌感染92例临床病理分析

目的 探讨胃及十二指肠溃疡并毛霉菌感染临床病理特征，方法 回顾性分析我院１２年来在外检中发现胃及十二指肠溃疡１５８６例，其中并发毛霉菌感染９２例，占５．８％，溃疡肉眼特征为一大，二深，三不整。病理组织学检查，找到毛霉菌菌丝，结果 胃及十二指肠溃疡在存在是继发毛霉菌感染的病理基础，结论 提出胃及十二指肠溃疡大，深，不整时，要警惕毛霉菌感染的可能，病理检查时也应对此有所考虑。     

Mucor cerebral abscess associated with intravenous drug abuse

We report on a case of a 26-year-old intravenous narcotic abuser with a primary cerebral mucormycotic abscess caused by Rhizopus oryzae. He was treated with a combination of intravenous and intraventricular amphotericin B and surgical drainage with a successful outcome. There was no evidence that his infection was acquired by the rhinocerebral route, it seems likely that he injected himself with a contaminated batch of narcotic or amphetamine. Mucormycosis presenting in this way has been described previously but this is only the second such case to survive. Early diagnosis and treatment is essential for a favourable outcome in this condition.     

A case of cutaneous mucormycosis in Shanghai, China

A 34-year-old female farmer suffered from localized cutaneous mucormycosis for 17 years. At the first admission, the lesion was a dull red plaque, about 7 x 9 cm in size with ulcerations, surrounded by some nodules on the dorsum of her right hand. General examination did not reveal abnormal findings except the skin lesion. Direct examination of skin scrapings in 10% KOH revealed broad, sparsely septate, branching hyphae. Histopathology showed many intradermal granulomata and microabscesses as well as mycelial elements comprising broad, distorted, ribbon-like strands. Some of them were phagocytized by multi-nucleated giant cells. Cultures revealed rapidly growing yellow colonies on Sabouraud dextrose agar medium at 25 degrees C. Sporangiophores branched in sympodia and the sporangia were globose, 35-60 microns in diameter. Their walls were deliquescent, but some of them were rather persistent. Columellae were mostly globose, 12-17 microns in diameter, up to 35 microns with collars. Sporangiospores were mainly ellipsoidal, 1.5-2.5 x 3-5 microns in size, but sometimes highly variable in size and shape. The maximum growth temperature of the isolate was 37 degrees C. The pathogenic organism isolated was tentatively identified as Mucor lusitanicus, which, as far as we know, has not been reported as a causative agent of cutaneous mucormycosis.     

刺囊毛霉对豆蔻明的生物转化研究(英文)

利用微生物转化方法对豆蔻明进行结构修饰,分离得到刺囊毛霉3.3450对豆蔻明的两个新的糖苷化转化产物,利用ESI-MS、1H NMR、13C NMR和2D NMR技术鉴定其结构分别为4-O-β-D-glucopyranosyl-6-hydroxy-2-methoxychalcone(1,4-GluC)和6-O-β-D-glucopyranosyl-4-hydroxy-2-methoxychalcone(2,6-GluC)。通过优化得到最佳转化条件:培养温度为28℃、转化时间为72 h、底物加样浓度为40 mg·mL-1。这是首次成功利用刺囊毛霉对豆蔻明进行微生物糖苷转化研究的报道。     

Successful treatment of mucormycosis in a renal allograft recipient

INTRODUCTION: Mucormycosis is a rare but potentially lethal fungal infection in renal allograft recipients with rhinocerebral mucormycosis is the most common presentation. The usual infection route is inhalation of the spores, but certain procedures such as intravenous cannulation and bladder catheterization are often the cause of infection. CASE: A 50-year-old female dermatologist received an allograft from an emotionally related living donor, 24-year-old male with the same blood group and 3/6 mismatches. After severe attack of acute vascular rejection associated with rupture graft, that was managed properly she developed rinocereral mucormycosis. It was diagnosed early and aggressively treated with amphoteracin B and carefully monitored with favourable graft and patient survival. Up to our knowledge, this is the first case of renal transplant with extrarenal-ethemoidal sinus-mucor infection associated with acute vascular rejection that in spite of aggressive anti-rejection therapies with methylprednisolone, rituximab and plasma exchange, had favourable outcome in terms of graft and patient survival. CONCLUSION: Mucormycosis in a renal allograft recipient is an extremely rare and potentially lethal complication. Aggressive anti-rejection therapy is a risk factor for the development of this unfavourable outcome. Early diagnosis, aggressive treatment with amphoteracin B and careful monitoring can be helpful in treating these patients and achieve favourable prognosis.     

Agrobacterium tumefaciens -mediated transformation of the zygomycete fungus Backusella lamprospora

The Agrobacterium -mediated transformation was adapted to Backusella lamprospora, a zygomycete fungus closely related to Mucor. The transforming plasmid contained the hygromycin B resistance (hph) and the green fluorescent protein (gfp) genes under the control of the regulator regions of the Mucor circinelloides gpd1 gene. The presence of the hph and gfp genes in the transformants was detected by PCR. The introduced genes could also be amplified directly from the spores of the transformants. The transformation efficiency was investigated by fluorescence microscopy of the transformed spores. A gradual decrease in the hygromycin B resistance was observed during several cultivation cycles: the growth of the transformants on the selection medium became slower, and the detection of the introduced gene became more difficult.