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Effect of nitrogen source on pullulan production by Aureobasidium pullulans grown in a batch bioreactor. 氮源对间歇式生物反应器培养普鲁兰小孢子菌产普鲁兰的影响。
Microbios Pub Date : 1999-01-01
T P West, B Strohfus
{"title":"Effect of nitrogen source on pullulan production by Aureobasidium pullulans grown in a batch bioreactor.","authors":"T P West,&nbsp;B Strohfus","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Pullulan production by Aureobasidium pullulans ATCC 201253 using selected nitrogen sources was studied in a medium using corn syrup as a carbon source. Independent of the corn syrup concentration present, the use of corn steep liquor or hydrolysed soy protein as a nitrogen source instead of ammonium sulphate did not elevate polysaccharide production by ATCC 201253 cells grown in an aerated, batch bioreactor containing 4 litres of medium. Pullulan production on corn steep liquor or hydrolysed soy protein as a nitrogen source became more comparable as the concentration of corn syrup was increased. Cell weights after 7 days of growth on any of the nitrogen sources were similar. The viscosity of the polysaccharide on day 7 was highest for cells grown on ammonium sulphate and 12.5% corn syrup. The pullulan content of the polysaccharide elaborated by ammonium sulphate-grown cells on day 7 decreased as the corn syrup level rose in the medium while the pullulan content of polysaccharide produced by cells grown on corn steep liquor or soytone generally increased.</p>","PeriodicalId":18494,"journal":{"name":"Microbios","volume":"99 394","pages":"147-59"},"PeriodicalIF":0.0,"publicationDate":"1999-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21441011","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
Biosynthesis and localization of glutamylendopeptidase from Bacillus intermedius strain 3-19. 中间芽孢杆菌菌株3-19谷氨酰胺内肽酶的生物合成与定位。
Microbios Pub Date : 1999-01-01
L A Gabdrakhmanova, E V Shakirov, N P Balaban, M R Sharipova, G N Rudenskaya, I B Leshchinskaya
{"title":"Biosynthesis and localization of glutamylendopeptidase from Bacillus intermedius strain 3-19.","authors":"L A Gabdrakhmanova,&nbsp;E V Shakirov,&nbsp;N P Balaban,&nbsp;M R Sharipova,&nbsp;G N Rudenskaya,&nbsp;I B Leshchinskaya","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The biosynthesis of glutamylendopeptidase from Bacillus intermedius strain 3-19 and localization of the enzyme in the bacterial cells was studied. The synthesis of the enzyme was suppressed by easily metabolizable carbon sources. Inorganic phosphate and NH4+ ions stimulated the production of glutamylendopeptidase. Complicated organic substrates such as casein, gelatine, and haemoglobin did not affect the biosynthesis of the enzyme. The divalent metallic ions Ca2+, Mg2+, Co2+ increased the production of glutamylendopeptidase while Zn2+, Cu2+, and Fe2+ reduced the biosynthesis of proteinase. The rate of synthesis of the enzyme increased when the rate of the bacterial growth decreased. The maximum enzyme activity in the culture fluid was determined at the stationary phase of growth. In the cells glutamylendopeptidase was bound to the cytoplasmic membrane, and the maximal enzyme activity was detected in the stationary growth phase. The results facilitated the development of a medium which yielded the maximum glutamylendopeptidase production by B. intermedius strain 3-19.</p>","PeriodicalId":18494,"journal":{"name":"Microbios","volume":"100 396","pages":"97-108"},"PeriodicalIF":0.0,"publicationDate":"1999-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21441016","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
Isolation, identification and analysis of antibacterial activity of soil streptomycetes isolates from north Jordan. 约旦北部土壤链霉菌的分离鉴定及抗菌活性分析。
Microbios Pub Date : 1999-01-01
I Saadoun, F al-Momani, H I Malkawi, M J Mohammad
{"title":"Isolation, identification and analysis of antibacterial activity of soil streptomycetes isolates from north Jordan.","authors":"I Saadoun,&nbsp;F al-Momani,&nbsp;H I Malkawi,&nbsp;M J Mohammad","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>A total of 90 different Streptomyces isolates were recovered from 36 soil samples and assessed for their antibacterial activity. Nine isolates were identified by the absence of an aerial mycelium. The rest were grouped into six colour series, namely grey, white, yellow, green, red and polymorphic colours (pink, orange or violet) with total numbers of 29, 18, 14, 8, 3 and 9, respectively. The isolates (68%) showed a reverse side culture pigmentation, 30% produced melanin and 25% produced other soluble pigments. Isolates (48%) were characterized by flexuous spore chains, 21% with spiral and 10% for each of the rectus and retinaculum apertum arrangement. The antibiotic activity against a wide range of bacteria was exhibited by 54% of the isolates which were effective against Bacillus subtilis (57%), Staphylococcus aureus (47%), Escherichia coli (24%), Klebsiella spp (16%), and Shigella spp (12%). The lowest activity (8%) was exhibited against Pseudomonas spp and Salmonella spp. The antibacterial activity of the isolates was divided into four groups according to the diameter of the inhibition zone produced. Groups 3 and 4 with larger inhibition zones indicated their potential as a possible source of novel antibiotics.</p>","PeriodicalId":18494,"journal":{"name":"Microbios","volume":"100 395","pages":"41-6"},"PeriodicalIF":0.0,"publicationDate":"1999-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21441664","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
In vitro activities of phenothiazine-type calmodulin antagonists against Mycobacterium leprae. 吩噻嗪型钙调素拮抗剂对麻风分枝杆菌的体外活性研究。
Microbios Pub Date : 1999-01-01
A M Dhople
{"title":"In vitro activities of phenothiazine-type calmodulin antagonists against Mycobacterium leprae.","authors":"A M Dhople","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Calmodulin-like protein has been established as the primary receptor for calcium in eukaryotic as well as prokaryotic cells. The calmodulin-calcium complex regulates a variety of enzymes including nucleotide phosphodiesterase. Recently, the presence of this protein in Mycobacterium leprae has been demonstrated and the effects of phenothiazine-type calmodulin antagonists on in vitro growth of M. leprae in a cell-free culture system were investigated. Two biochemical parameters were used to measure metabolic activity and growth of the organism. Among the six phenothiazine derivatives tested, trifluoperazine appeared to be the most potent in inhibiting the in vitro growth of M. leprae, with an MIC of 10 micrograms/ml. Chlorpromazine, triflupromazine and thioridazine were less active than trifluoperazine, with an MIC of 20 micrograms/ml each, while the other two, acetopromazine and fluphenazine, were totally ineffective even at 80 micrograms/ml. All four compounds inhibited the uptake of labelled acetate, glycine and thymidine by whole cells of M. leprae. This suggests that these phenothiazine derivatives have multiple sites of action and probably affect the synthesis of lipids, proteins and DNA.</p>","PeriodicalId":18494,"journal":{"name":"Microbios","volume":"98 390","pages":"113-21"},"PeriodicalIF":0.0,"publicationDate":"1999-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21479454","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
Appearance in Japan of highly macrolide-resistant Escherichia coli producing macrolide 2'-phosphotransferase II. 产生大环内酯2'-磷酸转移酶II的高大环内酯耐药大肠杆菌在日本出现。
Microbios Pub Date : 1999-01-01
K Taniguchi, A Nakamura, K Tsurubuchi, A Ishii, K O'Hara, T Sawai
{"title":"Appearance in Japan of highly macrolide-resistant Escherichia coli producing macrolide 2'-phosphotransferase II.","authors":"K Taniguchi,&nbsp;A Nakamura,&nbsp;K Tsurubuchi,&nbsp;A Ishii,&nbsp;K O'Hara,&nbsp;T Sawai","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Escherichia coli CU1, a clinical isolate recovered in Japan in 1997, was found to be highly-resistant to both 14-membered and 16-membered ring macrolide antibiotics. A crude extract prepared from strain CU1 inactivated 14-, 15- and 16-membered ring macrolides in the presence of ATP and the Rf value of inactivated oleandomycin was identical to that of oleandomycin 2'-phosphate. This suggested that strain CU1 produced the enzyme macrolide 2'-phosphotransferase [MPH(2')]. Substrate specificity of the crude enzyme from strain CU1 against 14-, 15- and 16-membered ring macrolides was basically similar to that of MPH(2')II from strain BM2506, differing in that the former more effectively inactivated roxithromycin and tylosin. Subsequent attempts were made to clone the novel mph gene encoding for MPH(2') in strain CU1. The mph gene carried by strain CU1 was located on nontransmissible plasmid DNA, designated pCU001. Its molecular weight, estimated by agarose electrophoresis, was approximately 57 kD. The DNA sequence of the cloned mph gene from the Japanese isolate CU1 was identical to that of mphB, which until now had only been recovered in France. The variance in the substrate specificity of MPH(2')II from each strain led us to speculate that other factors in the reaction affect the enzymatic inactivation activity.</p>","PeriodicalId":18494,"journal":{"name":"Microbios","volume":"97 388","pages":"137-44"},"PeriodicalIF":0.0,"publicationDate":"1999-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21280448","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
Variations in the gene for vacuolating toxin, vacA, in Japanese isolates of Helicobacter pylori. 日本幽门螺杆菌中空泡毒素vacA基因的变异。
Microbios Pub Date : 1999-01-01
T Ueda, M Kawaguchi, T Saito, M Ishigaki, H Hamashima, M Sasatsu, T Arai
{"title":"Variations in the gene for vacuolating toxin, vacA, in Japanese isolates of Helicobacter pylori.","authors":"T Ueda,&nbsp;M Kawaguchi,&nbsp;T Saito,&nbsp;M Ishigaki,&nbsp;H Hamashima,&nbsp;M Sasatsu,&nbsp;T Arai","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Each of 284 strains of Helicobacter pylori which had been isolated in Japan was shown, by use of the polymerase chain reaction (PCR), to be positive for the vacA genes. The amplified vacA genes generated by PCR were classified into six classes (five for the clinical isolates, and one which corresponded to the standard strains). Endoscopic analysis revealed that cases of gastritis were most likely to be associated with class D, while none were associated with class A. The patterns of products of PCR obtained from the Japanese isolates were compared with theoretical patterns derived from sequences of vacA which had been reported previously. The nucleotide sequences of amplified fragments of vacA from representative strains in each class were determined and compared with those of previously reported vacA genes.</p>","PeriodicalId":18494,"journal":{"name":"Microbios","volume":"97 388","pages":"165-78"},"PeriodicalIF":0.0,"publicationDate":"1999-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21280966","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
Purification and characterization of an arylamine N-acetyltransferase in the nematode Enterobius vermicularis. 线虫中一种芳胺n -乙酰转移酶的纯化及特性研究。
Microbios Pub Date : 1999-01-01
J G Chung
{"title":"Purification and characterization of an arylamine N-acetyltransferase in the nematode Enterobius vermicularis.","authors":"J G Chung","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>N-acetyltransferase (NAT) activities were determined by incubation of Enterobius vermicularis cytosols with 2-aminofluorene (2-AF) as the substrate followed by high pressure liquid chromatography assays. The NAT activity from E. vermicularis was found to be 0.41 +/- 0.08 nmol/min/mg protein for 2-AF. The apparent K(m) and Vmax values obtained were 0.81 +/- 0.11 mM and 2.25 +/- 0.22 nmol/min/mg protein respectively, for 2-AF. The optimal pH value for the enzyme activity was 7.5 for 2-AF. The optimal temperature for enzyme activity was 37 degrees C for the 2-AF substrate. The molecular weight of NAT from E. vermicularis was 44.9 kD. Among a series of divalent cations and salts, Zn2+, Ca2+, and Fe2+ were the most potent inhibitors. Of the protease inhibitors, only ethylenediaminetetraacetic acid significantly protected the NAT. Iodoacetate, in contrast to other agents, markedly inhibited NAT activity. This report is the first demonstration of acetyl coenzyme A-dependent arylamine NAT activity in E. vermicularis and extends the number of phyla in which this activity has been found.</p>","PeriodicalId":18494,"journal":{"name":"Microbios","volume":"98 389","pages":"15-25"},"PeriodicalIF":0.0,"publicationDate":"1999-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21280969","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
An evaluation of chromogenic substrates for characterization of serine protease produced by pathogenic Vibrio alginolyticus. 致病性溶藻弧菌丝氨酸蛋白酶的显色底物评价。
Microbios Pub Date : 1999-01-01
F R Chen, P C Liu, K K Lee
{"title":"An evaluation of chromogenic substrates for characterization of serine protease produced by pathogenic Vibrio alginolyticus.","authors":"F R Chen,&nbsp;P C Liu,&nbsp;K K Lee","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Four chromogenic substrates for characterizing serine protease of Vibrio alginolyticus were evaluated. The protease activity of bacterial extracellular products, or the fractions of 33 kD protease purified by the AKTA purifier system with various columns, was completely inhibited by ethylenediamine tetra-acetic acid, ethylene glycol-bis(beta-amino-ethyl ether) N,N,N',N'-tetraacetic acid (EGTA), antipain and phenylmethylsulphonyl fluoride (PMSF) using water-soluble substrates (azoalbumin and azocasein). It was only completely inhibited by antipain and PMSF using water-insoluble substrates (azocoll and hide powder azure). The protease activity was not, or only partially, inhibited by 1,10-phenanthroline and sodium dodecyl sulphate (SDS) using all four substrates. Since chelating agents and 1,10-phenanthroline are commonly employed as inhibitors to identify metalloprotease, the two water-soluble substrates may not be appropriate for this purpose, except for using 1,10-phenanthroline as an inhibitor. Chelating agents may be still applicable as inhibitors using water-insoluble substrates and 1,10-phenanthroline is highly recommended in the characterization for metalloprotease to avoid confusion. In the present study, the 33 kD protease was further confirmed as an SDS-resistant serine protease and not a metalloprotease.</p>","PeriodicalId":18494,"journal":{"name":"Microbios","volume":"98 389","pages":"27-34"},"PeriodicalIF":0.0,"publicationDate":"1999-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21280970","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
Unchanged characteristics of Helicobacter pylori during its morphological conversion. 幽门螺杆菌形态转化过程中特征不变。
Microbios Pub Date : 1999-01-01
P Y Zheng, J Hua, H C Ng, B Ho
{"title":"Unchanged characteristics of Helicobacter pylori during its morphological conversion.","authors":"P Y Zheng,&nbsp;J Hua,&nbsp;H C Ng,&nbsp;B Ho","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Helicobacter pylori strains RH 54 and NCTC 11637 were grown in brain-heart infusion broth up to 56 days, and the coccoid form was obtained during prolonged incubation. Two morphological types of coccoids were observed, one of which was electron-dense and had an intact cellular membrane and flagella, indicating that it was likely to be viable. The other coccoid form was sphaeroblast-like and weakly stained, showing features of degeneration. Catalase activity was positive for aged cultures even up to 160 days. Sodium dodecyl sulphate polyacrylamide gel electrophoresis showed that most of the protein bands appeared to be similar in both the spiral and coccoid forms. In addition, Lewis blood group antigens were detected in cultures of up to 8 weeks. Furthermore, two sets of primers for the vacA and cagA genes were used in polymerase chain reaction, and these two important genes remained conserved in both the spiral and coccoid forms. The present study shows that the coccoid form of H. pylori retained many important characteristics present in the spiral form despite the morphological conversion, and thus supports the notion that some of the coccoid forms of H. pylori are likely to be viable.</p>","PeriodicalId":18494,"journal":{"name":"Microbios","volume":"98 389","pages":"51-64"},"PeriodicalIF":0.0,"publicationDate":"1999-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21280971","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
Characterization and analysis of antibiotic activity of some aquatic actinomycetes. 几种水生放线菌的抗菌活性鉴定与分析。
Microbios Pub Date : 1999-01-01
I Saadoun, K M Hameed, A Moussauui
{"title":"Characterization and analysis of antibiotic activity of some aquatic actinomycetes.","authors":"I Saadoun,&nbsp;K M Hameed,&nbsp;A Moussauui","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Nine different isolates of aquatic actinomycetes identified as Streptomyces spp. were studied for their morphological and cultural characteristics. One of these isolates (C4-S, Streptomyces violaceusniger) was extensively studied for its inhibitory effect against a wide range of Gram-positive, Gram-negative bacteria, Mycobacterium vaccae ATCC 29678, Candida albicans and several food associated filamentous fungi and yeasts. Most of these were characterized by flexous sporophore morphology and their inability to produce cultural pigments. Bioassay results indicated that S. violaceusniger of 10 days culture age was highly active against Gram-positive cocci and bacilli with an inhibition zone of 16-25 mm, and slightly active against M. vaccae ATCC 29678 with an inhibition zone of 5-10 mm. The inhibitory effect was slight against Escherichia coli, Aspergillus niger 1 and C. albicans with an inhibition zone of 8-10 mm for each of them. There was no inhibitory effect of S. violaceusniger against other Gram-negative bacteria, filamentous fungi and yeast. The nature of the active molecule produced by S. violaceusniger showed a maximum absorption in the UV region at 210-260 nm.</p>","PeriodicalId":18494,"journal":{"name":"Microbios","volume":"99 394","pages":"173-9"},"PeriodicalIF":0.0,"publicationDate":"1999-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21441013","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
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