SAAS bulletin, biochemistry and biotechnology最新文献_第3页

Analysis of a mycotoxin gene cluster in Aspergillus nidulans. 细粒曲霉一个霉菌毒素基因簇的分析。

SAAS bulletin, biochemistry and biotechnology Pub Date : 1995-01-01

N P Keller, T H Adams

{"title":"Analysis of a mycotoxin gene cluster in Aspergillus nidulans.","authors":"N P Keller, T H Adams","doi":"","DOIUrl":"","url":null,"abstract":"Aspergillus nidulans has functioned as a model system for the study of fungal genetics since the 1950s. Application of methodologies ranging from Mendelian genetics to the most sophisticated molecular biological techniques have resulted in a detailed understanding of genes and pathways involved in primary metabolism, secondary metabolism and development in A. nidulans. We have taken advantage of this background in developing A. nidulans as a genetic system to study the molecular mechanisms regulating aflatoxin biosynthesis. Aflatoxin, a carcinogenic polyketide, is the product of a lengthy biochemical pathway found in the asexual spp., A. flavus and A. parasiticus. A. nidulans possesses most if not all of this pathway and produces sterigmatocystin, the penultimate precursor of the aflatoxin pathway. We have identified a approximately 60 kb cluster of genes in A. nidulans whose products are involved in sterigmatocystin biosynthesis. This cluster contains at least 20 genes proposed to encode both enzymatic activities and regulatory proteins. Our results have shown that at least some of these genes are functionally conserved between A. nidulans, A. flavus and A. parasiticus, and that they are regulated in similar ways. Further studies of sterigmatocystin regulation in A. nidulans should yield information transferable to studies of (i) secondary metabolism in other filamentous fungi and (ii) aflatoxin regulation in A. flavus and A. parasiticus in particular.","PeriodicalId":77373,"journal":{"name":"SAAS bulletin, biochemistry and biotechnology","volume":"8 ","pages":"14-21"},"PeriodicalIF":0.0,"publicationDate":"1995-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18554608","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Biomass degrading enzymes from anaerobic rumen fungi. 厌氧瘤胃真菌的生物质降解酶。

SAAS bulletin, biochemistry and biotechnology Pub Date : 1995-01-01

H Chen, X L Li, L G Ljungdahl

引用次数: 0

Telluromethionine in structural biochemistry. 结构生物化学中的碲蛋氨酸。

SAAS bulletin, biochemistry and biotechnology Pub Date : 1995-01-01

J O Boles, L Lebioda, R B Dunlap, J D Odom

引用次数: 0

Gene expression in a temperature-sensitive mutant of the cell cycle. 细胞周期温度敏感突变体中的基因表达。

SAAS bulletin, biochemistry and biotechnology Pub Date : 1994-01-01

R R Hirschhorn

{"title":"Gene expression in a temperature-sensitive mutant of the cell cycle.","authors":"R R Hirschhorn","doi":"","DOIUrl":"","url":null,"abstract":"The proliferative response of mammalian fibroblasts to growth stimulation requires gene expression, including an increase in RNA synthesis. Vimentin, a class III intermediate filament, has been shown to be encoded by a growth-regulated gene whose mRNA levels increase after serum stimulation of quiescent hamster fibroblasts. This induction is a consequence of increased vimentin-specific transcriptional activity and is followed by the accumulation of stable cytoplasmic transcripts which are translated into polymerized filaments. The expression of vimentin in a G1-specific temperature-sensitive cell-cycle mutant growth-stimulated at the restrictive temperature is strikingly different from the growth-regulated expression observed at the nonrestrictive temperature. While the vimentin gene is transcriptionally activated at the restrictive temperature, most of the transcripts accumulate in the nucleus and are not transported to the cytoplasm. Those transcripts that are cytoplasmic have a decreased stability and are not translated into protein. Vimentin gene expression in the parent cell line at both the restrictive and nonrestrictive temperatures is virtually identical, suggesting that the altered expression of vimentin in the cell-cycle mutant at the restrictive temperature is related to the G1-specific block and not to the elevated temperature. The expression of the other growth-regulated genes is currently being investigated in the temperature-sensitive cell cycle mutant to determine if this effect is vimentin-specific or specific for a subclass of growth-regulated genes.","PeriodicalId":77373,"journal":{"name":"SAAS bulletin, biochemistry and biotechnology","volume":"7 ","pages":"31-5"},"PeriodicalIF":0.0,"publicationDate":"1994-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18765553","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Inhibition of O6-methylguanine-DNA methyltransferase in HeLa S3 cells by antisense oligodeoxynucleotides. 反义寡脱氧核苷酸对HeLa S3细胞o6 -甲基鸟嘌呤- dna甲基转移酶的抑制作用

SAAS bulletin, biochemistry and biotechnology Pub Date : 1994-01-01

S K Ballal, K Isham, R S Foote

引用次数: 0

Current research to develop the entomopathogen Bacillus thuringiensis for horn fly control. 昆虫病原苏云金芽孢杆菌防治角蝇的研究进展。

SAAS bulletin, biochemistry and biotechnology Pub Date : 1994-01-01

K B Temeyer

引用次数: 0

Recombinant vaccine development: a novel approach to ectoparasite control. A review of development of a recombinant vaccine for hypodermosis based on hypodermin A. 重组疫苗研制:控制体外寄生虫的新方法。基于浅皮素A的重组皮下病疫苗的研究进展。

SAAS bulletin, biochemistry and biotechnology Pub Date : 1993-01-01

K B Temeyer, J H Pruett, I Kuhn, J Files

引用次数: 0

Detection of Borrelia burgdorferi in tissues of experimentally infected Peromyscus leucopus by the polymerase chain reaction. 聚合酶链反应检测实验感染的白斑过密菌组织中的伯氏疏螺旋体。

SAAS bulletin, biochemistry and biotechnology Pub Date : 1993-01-01

N Ge, G L Murphy, A A Kocan

引用次数: 0

Host-specific transcription of baculovirus genes. 杆状病毒基因的宿主特异性转录。

SAAS bulletin, biochemistry and biotechnology Pub Date : 1993-01-01

S L Bilimoria, Z Demirbag, H Ng

{"title":"Host-specific transcription of baculovirus genes.","authors":"S L Bilimoria, Z Demirbag, H Ng","doi":"","DOIUrl":"","url":null,"abstract":"We examined the differential replication of Autographa californica multicapsid nuclear polyhedrosis virus (AcMNPV; Family: Baculoviridae) in Spodoptera frugiperda (SF) and Bombyx mori (BM) cell lines. Our previous studies have shown that infection of BM cells is abortive; infectious progeny is not produced, and although virogenic stroma is produced, complete virions or inclusion bodies are not assembled. We designed the present study to determine the extent of infected-cell-specific polypeptides (ICSPs) and viral DNA synthesis in the abortive infection and to see if restriction of virus replication in BM cells is due to a block at the transcriptional level. Pulse-labeling studies showed that a majority of the ICSPs detected in productive SF cells were not synthesized in BM cells. Many of these ICSPs were virion components. Viral DNA replicated in BM cells but more slowly and at a much lower level than in SF cells. Northern blot analysis showed that i) AcMNPV immediate-early gene (IE-1) was transcribed in BM cells at higher levels than in SF cells; ii) a delayed-early gene (dnapol) and a late gene (cap) were transcribed at much lower levels in the abortive infection; and iii) a very late gene (polh) was transcribed at extremely low levels in BM cells. We conclude that virus replication in BM cells is primarily restricted during or prior to the delayed-early stage and occurs at the transcriptional level. It appears that the late and very late effects observed are consequences of the primary block.","PeriodicalId":77373,"journal":{"name":"SAAS bulletin, biochemistry and biotechnology","volume":"6 ","pages":"1-7"},"PeriodicalIF":0.0,"publicationDate":"1993-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18767286","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Differential recovery of mRNA transcripts using acid organic extraction techniques: quantification of abl mRNA abundance in the blowfly, Calliphora erythrocephala. 利用酸性有机萃取技术对mRNA转录物的差异回收:定量测定红头苍蝇的abl mRNA丰度。

SAAS bulletin, biochemistry and biotechnology Pub Date : 1993-01-01

N Huang, D S Durica

引用次数: 0