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1.
Spherical, osmotically fragile protoplasts were obtained from the mycelium of Penicillium paxilli. The lytic enzymes were derived from the culture filtrate of P. purpurogenum grown on disintegrated mycelium of P. paxilli. Maximum numbers of protoplasts were released from 36 h mycelium, using 1 M sorbitol as an osmotic stabilizer, at pH 5.8, after 2 h incubation with lytic enzymes at 30 degrees C.  相似文献   

2.
Infections caused byPenicillium chrysogenum are rare. The first case of posttraumatic endophthalmitis caused by this saprophytic fungus is reported. Therapy with amphotericin B and topical natamycin eradicated the organism.  相似文献   

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The taxonomy of the important mycotoxigenic species Penicillium viridicatum and P. verrucosum was reviewed to clarify disagreements relating to the three P. viridicatum groups erected by Ciegler and coworkers (A. Ciegler, D. I. Fennell, G. A. Sansing, R. W. Detroy, and G. A. Bennett, Appl. Microbiol. 26:271-278, 1973) and the mycotoxins produced by them. Cultures derived from the types of these two species and authentic cultures from each group and from many other sources were examined culturally, microscopically, and for mycotoxin production. It was concluded that P. viridicatum group II has affinities with P. verrucosum and not with P. viridicatum, as indicated by J. I. Pitt in the 1979 monograph (The Genus Penicillium and Its Teleomorphic States Eupenicillium and Talaromyces). As a result of this study it can now be unequivocally stated that the mycotoxins ochratoxin A and citrinin are not produced by P. viridicatum. Of species in subgenus Penicillium, only P. verrucosum is known to produce ochratoxin A.  相似文献   

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Nine major cellulolytic enzymes were isolated from a culture broth of a mutant strain of the fungus Penicillium verruculosum: five endo-1, 4-β-glucanases (EGs) having molecular masses 25, 33, 39, 52, and 70 kDa, and four cellobiohydrolases (CBHs: 50, 55, 60, and 66 kDa). Based on amino acid similarities of short sequenced fragments and peptide mass fingerprinting, the isolated enzymes were preliminary classified into different families of glycoside hydrolases: Cel5A (EG IIa, 39 kDa), Cel5B (EG IIb, 33 kDa), Cel6A (CBH II, two forms: 50 and 60 kDa), Cel7A (CBH I: 55 and 66 kDa), Cel7B (EG I: 52 and 70 kDa). The 25 kDa enzyme was identical to the previously isolated Cel12A (EG III). The family assignment was further confirmed by the studies of the substrate specificity of the purified enzymes. High-molecular-weight forms of the Cel6A, Cel7A, and Cel7B were found to possess a cellulose-binding module (CBM), while the catalytically active low-molecular-weight forms of the enzymes, as well as other cellulases, lacked the CBM. Properties of the isolated enzymes, such as substrate specificity toward different polysaccharides and synthetic glycosides, effect of pH and temperature on the enzyme activity and stability, adsorption on Avicel cellulose and kinetics of its hydrolysis, were investigated.  相似文献   

7.
Summary A 1,4--d-glucan glucohydrolase (EC 3.2.1.74) was isolated from culture filtrates of Penicillum funiculosum and purified by isoelectric focussing. The purified enzyme was homogeneous as indicated by electrophoresis on sodium dodecyl sulphate-polyacrylamide gels. The enzyme had a molecular weight of 20 000 and the pI was 4.45. The hydrolysis of Avicel by the purified enzyme and culture broth using equal amounts of Walseth units were comparable. The glucohydrolase did not act in synergism with endoglucanase or cellobiohydrolase from the same culture. The enzyme had little ability to attack carboxymethyl cellulose. It showed activity towards Avicel, Walseth cellulose and cellooligosaccharides (G3-G5), producing glucose as the end product, indicating that the enzyme is a -1–4 glucan glucohydrolase. The enzyme exhibited transglucosidase activity, producing higher oligosaccharides from cellobiose.NCL Communication no. 3899  相似文献   

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马尔尼菲青霉菌的鉴定   总被引:1,自引:0,他引:1  
为了提高马尔尼菲青霉菌的分离率和鉴定的正确率,通过培养检查特征性的菌丝和观察菌落形态,通过形态学观察其在骨髓和外周血以及PAS染色的形态。马尔尼菲青霉菌为双相菌,霉菌型菌落可发现特征性的扫帚状菌丝,沙保罗培养3 d后产生水溶性玫瑰色素;骨髓和外周血细胞内外均可发现孢子;PAS染色可见菌体呈圆形、椭圆形或腊肠状,大小不一,约为2~8μm,胞壁染红色且清楚连续,在腊肠状的细胞内可见一明显的横隔,胞质不易着色。鉴定结论:特征性的扫帚状菌丝;骨髓和外周血细胞内外均可发现孢子;水溶性玫瑰色素;PAS染色对其有鉴定价值。  相似文献   

10.
Two new carboxylic acids, tanzawaic acid E (1) and F (2) in addition to the unknown benzopyran 3,7-dimethyl-1,8-dihydroxy-6-methoxy-isochroman (3), and the known mycotoxin 3,7-dimethyl-8-hydroxy-6-methoxyisochroman (4) were produced by a marine-derived strain of Penicillium steckii isolated from an unidentified tunicate. The carboxylic acids and the benzopyran were identified on the basis of mass spectrometry, and one and two dimensional NMR spectroscopic techniques. The structures 1 and 2 resemble tanzawaic acid A-D, previously isolated from Penicillium citrinum. Screening of isolates of species related to P. citrinum and P. steckii showed that P. citrinum (25 isolates) consistently produced citrinin and tanzawaic acid A, P. steckii (18 isolates) produced isochroman toxins (except 2) and tanzawaic acid E, P. sizovae consistently produced tanzawaic acid A, P. corylophilum (10 isolates) produced citreoisocoumarinol and P. sumatrense (15 isolates) always produced curvularin.  相似文献   

11.
Two diketopiperazine alkaloids, rugulosuvines A and B (tryptophan and phenylalanine are their precursors), were isolated and purified from a culture liquid of Penicillium rugulosumVKM F-352 and Penicillium piscariumVKM F-325 fungi. Physical and physicochemical studies showed the absolute structure of rugulosuvine A. The absolute structure of rugulosuvine B was demonstrated to be identical to that of rugulosuvine A.  相似文献   

12.
Transformation in Penicillium chrysogenum   总被引:3,自引:0,他引:3  
F Sánchez  M Lozano  V Rubio  M A Pe?alva 《Gene》1987,51(1):97-102
An auxotrophic mutant of Penicillium chrysogenum with a DNA rearrangement that affects the trpC region has been transformed to the Trp+ phenotype by using a plasmid that contains the trifunctional wild-type gene. A frequency of 40-80 transformants per microgram of input DNA was usually achieved. A low frequency of plasmid integration at the recipient mutated trpC gene was detected; however, most of the transformants integrated the plasmid DNA elsewhere into the genome. Some of the transformants contain multiple rearranged copies of the vector integrated in a tandem fashion.  相似文献   

13.
The taxonomy of the important mycotoxigenic species Penicillium viridicatum and P. verrucosum was reviewed to clarify disagreements relating to the three P. viridicatum groups erected by Ciegler and coworkers (A. Ciegler, D. I. Fennell, G. A. Sansing, R. W. Detroy, and G. A. Bennett, Appl. Microbiol. 26:271-278, 1973) and the mycotoxins produced by them. Cultures derived from the types of these two species and authentic cultures from each group and from many other sources were examined culturally, microscopically, and for mycotoxin production. It was concluded that P. viridicatum group II has affinities with P. verrucosum and not with P. viridicatum, as indicated by J. I. Pitt in the 1979 monograph (The Genus Penicillium and Its Teleomorphic States Eupenicillium and Talaromyces). As a result of this study it can now be unequivocally stated that the mycotoxins ochratoxin A and citrinin are not produced by P. viridicatum. Of species in subgenus Penicillium, only P. verrucosum is known to produce ochratoxin A.  相似文献   

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Conidium ontogeny in Penicillium   总被引:1,自引:0,他引:1  
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A new meroterpenoid, austalide H acid ethyl ester (1), 5-(2′,4′-dihydroxy-6′-methylphenyl)-3-methylfuran-2-carboxylic acid (2), 5-(2′-hydroxy-6′-methylphenyl)-3-methylfuran-2-carboxylic acid (3) and 5-((6′-methyl-4′-oxo-3′,4′-dihydro-2H-pyran-2′-yl)methyl)-3-methylfuran-2-carboxylic acid (4), along with six known compounds, austalides H, J, K, and P (58), questin (9) and sulochrin (10) were isolated from the lipophilic extract of the alga-derived fungi Penicillium thomii KMM 4645 and Penicillium lividum KMM 4663. The structures of the isolated compounds were determined based on spectroscopic methods. The austalides showed significant inhibitory activity against endo-1,3-β-d-Glucanase from a crystalline stalk of the marine mollusk Pseudocardium sachalinensis.  相似文献   

18.
The type strains Penicillium clavigerum VKM F-447 and P. commune VKM F-3233 are found to produce fumigaclavines A and B. Of the seven other strains of these species, only two strains, P. commune VKM F-3088 and F-3491, possess the ability to synthesize these alkaloids. It is suggested that the five other strains under study either lost such an ability or require very specific conditions for the synthesis of these alkaloids.  相似文献   

19.
Seven new species of Penicillium Link ex Fries and a new variety of Penicillium novae-caledoniae Smith are described and illustrated. Four of them have been recovered from the air in Madrid, Spain, one from beech leaves litter in a beech forest near Nancy, France, two from sandy soils in Madrid, and one from an andosol in the Spanish Province of Navarra. They clearly differ from all species of the genus described so far and are, therefore, described and proposed as new taxa: Penicillium turolense sp. nov., Penicillium murcianum sp. nov., Penicillium ovetense sp. nov., Penicillium asturianum sp. nov., Penicillium onobense sp. nov., Penicillium castellonense sp. nov., Penicillium aragonense sp. nov., and Penicillium novae-caledoniae Smith, var. album var. nov.  相似文献   

20.
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