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1.
An undescribed species of Penicillium was isolated in August 1982 from sand dunes located at the Arches National Monument, Utah, USA. It clearly differs from all species of the genus described so far and is, therefore, described and proposed as a new taxon: Penicillium flavido-stipitatum sp. nov.  相似文献   

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A new species ofPenicillium belonging to theP.funiculosum series of the Biverticillata — Symmetrica section is described from the rhizosphere ofBrassica campestris var.toria. The species is characterized by the presence of penicilli with 8–12 metulae on malt-extract agar and a very limited sporulation on Czapek-Dox agar. The species is namedPenicillium korosum on account of its broom-like penicilli.The authors are grateful to Prof. Kenneth B. Raper, Dr. Amelia Stolk and Dr. D. B. Prest for valuable comments, to Rev. Fr. Prof. Dr. Santapau and Fr. Ignatius Menezes for latinizing the specific diagnosis and to the Council of Scientific and Industrial Research, India, for financial assistance.  相似文献   

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Mycotoxin from Penicillium puberulum.   总被引:1,自引:0,他引:1  
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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   

6.
A strain of Penicillium funiculosum, isolated in this laboratory, produced in high yield both endo- and exo-glucanases and beta-glucosidases, which were suitable for the saccharification of cellulosic materials. The isolation of the beta-glucosidase of this organism, which differs from other beta-glucosidases of fungi in its substrate specificity, by preparative electrophoresis, is described in this article. The organism was grown on a lactose-casein medium and the culture filtrate concentrated by ammonium sulfate precipitation and dialysis. Electrophoresis was carried out on large slabs of polyacrylamide gel in an anodicrun in the presence of borate at pH 7. After elution of active fractions, a cathodic run was made at pH 6.0. Two precipitations with ammonium sulfate resulted in a homogeneous enzyme (specific activity 174 IU/mg). A second isozyme was also produced by P. funiculosum on cellulose-wheat bran medium. This isozyme was purified by electrophoresis at pH 7.0 in the absence of borate and was obtained free from other isozymes of beta-glucosidase and cellulases.  相似文献   

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An isolate of Penicillium biforme Thom produced rugulovasines A and B. An isolate of Penicillium rubrum Stoll produced rugulovasines A and B and also chlororugulovasines A and B. Both fungi represent new sources of the rugulovasines.  相似文献   

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Viruses of Penicillium and Aspergillus species.   总被引:1,自引:0,他引:1       下载免费PDF全文
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11.
Uberto Tosco 《Plant biosystems》2013,147(3-4):441-449
Summary

The A., with a series of controls and investigations, accomplished on different groups of Oranges and following various forms of artificial infection with Penicillium digitatum and Penicillium italicum, renders evident the different reactions that these moulds have with regard to the resistance of the cuticle and the epidermic and under-epidermic stratums of the peel of the controlled fruits. Moreover the A. confirms that both the P. digitatum and the P. italicum can act as «parasite of injury» and as «parasite of contact».  相似文献   

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One new species of Penicillium Link ex Gray nom. cons. prop. is described and illustrated. This species has been recovered from samples of sandy soil under pine trees. It differs from all species of the Genus described so far and is, therefore, considered and proposed as new taxon: Penicillium caerulescens n. sp.  相似文献   

16.
The product distributions resulting from the action of Penicillium lilacinum dextranase on end-labelled oligosaccharides of the isomaltose series have been determined. The initial rates of formation of labelled products were measured for isomaltotriose up to isomalto-octaose, and the molar proportions and radioactivity of the final products from isomaltotriose up to isomaltohexaose were determined. D-Glucose was released only from isomaltotriose and isomaltotetraose, by hydrolysis of the first linkage from the reducing end (linkage 1); the terminal bonds of higher members of the series were not attacked. All oligosaccharides except isomaltotriose were hydrolyzed at more than one linkage. The main points of attack on isomaltotetraose up to isomalto-octaose were at linkage 2, and at the third linkage from the non-reducing end; these two positions coincide for isomaltopentaose. The degradation of isomaltotriose up to isomalto-octaose was entirely hydrolytic. The enzyme also catalyzed an extremely slow, concentration-dependent degradation of isomaltose, and this may have occurred via a condensation to isomaltotetraose, followed by hydrolysis of linkage 1 to give D-glucose and isomaltotriose.  相似文献   

17.
Compounds structurally related to lysine were tested against Penicillium chrysogenum Wis. 54-1255 for inhibition of growth, sporulation, and penicillin formation. This strain is relatively resistant to lysine analogs. The compounds that were the more active inhibitors of growth and whose activities were reversed by L-lysine were diaminohexynoic acid, N-epsilon-methyllysine, N-alpha-methyllysine, and diaminopimelic acid. These four compounds also inhibited sporulation, which was more sensitive to inhibition than growth was. Analogs strongly inhibiting benzyl-penicillin formation by resting mycelia were diaminohexynoic acid and N-epsilon-methyllysine. The action of the most active analog (diaminohexynoic acid) on penicillin synthesis was reversed by DL-alpha-aminoadipic acid.  相似文献   

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Conidiogenesis and secondary metabolism in Penicillium urticae.   总被引:10,自引:2,他引:8       下载免费PDF全文
Submerged cultures of Penicillium urticae (NRRL 2159A) produced the antibiotics patulin and griseofulvin when grown in a glucose-nitrate medium. A high concentration of calcium (i.e., 68 mM) inhibited the production of both antibiotics while stimulating conidiogenesis. Conidial mutants that were defective in an early stage of conidiogenesis produced markedly less patulin, even under growth conditions that favored secondary metabolism. A mutant which lacked the ability to produce the patulin pathway metabolites m-cresol, toluquinol, m-hydroxybenzyl-alcohol, m-hydroxybenzaldehyde, gentisaldehyde, gentisyl alcohol, gentisic acid and patulin, as well as the pathway enzyme m-hydroxybenzyl-alcohol dehydrogenase, still produced yields of conidia that were equivalent to or greater than those of the parent strain. Other mutants which were blocked at later steps of the patulin pathway also produced conidia. These results indicate that patulin and the other related secondary metabolites noted above are not a prerequisite to conidiogenesis in P. urticae. Environmental and developmental factors such as calcium levels and conidiogenesis do, however, indirectly affect the production of patulin pathway metabolites.  相似文献   

20.
In surface culture of Penicillium simplicissimum, verruculogen was shown to be biosynthesized from the intact carbon skeletons of tryptophan and proline, isoprenoid derivatives of mevalonic acid, and a methyl group donated by methionine. Selected radiolabeled precursors (1 mCi) pulse-fed at the optimum stage of fermentation yielded verruculogen (specific activity, 5.89 X 10(2) microCi mmol-1) labeled in the prolyl and isoprenyl regions of the molecule and suitable for metabolic studies.  相似文献   

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