摘要:

The DNA sequence of thephe Bgene isolated from a chromosome of the phenol degrading bacteriumPseudomonas putidaBH is identical to that of thedmp Bgene from the phenol degradative plasmid, pVI150. Catechol 2,3‐dioxygenase encoded byphe Bshowed similar substrate specificity to that ofxylE. However, Phe B has much smallerKmvalues than Xyl E, indicating that Phe B is useful for treatment of low concentrations of catechol derivatives in waste wate

ISSN:0266-8254    

DOI:10.1111/j.1472-765X.1994.tb00938.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

Random amplified polymorphic DNA (RAPD) profiling ofLegionella pneumophilaby PCR can be used to provide a simple and efficient comparison of clinical and environmental isolates. RAPD profiling is quicker and cheaper to perform than restriction fragment length polymorphism (RFLP) typing, eliminating the need for blotting, hybridization and detection. For some isolates, RAPD profiling is more discriminatory than RFLP typing, being able to distinguish between isolates with identical RFLP types.

ISSN:0266-8254    

DOI:10.1111/j.1472-765X.1994.tb00939.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

Four therapeutically important strains ofLactobacillus acidophilusdesignated as R, 301, 1899 and NCFM were screened for the presence of plasmids. Two lysis methods were used for the isolation of plasmid DNA: an alkaline method and a more gentle technique. It was found that the gentle lysis method yielded better plasmid DNA both quantitatively and qualitatively. All four strains studied apparently possess plasmids. The strains 301 and NCFM possessed one plasmid each, with a size of 4.2 kb, whereas R possessed three plasmids (3.5, 2.4 and 2.1 kb) and 1899 possessed two plasmids (4.1 and 4.2 kb). Restriction analysis revealed that the plasmid DNA from strain R was cleaved byBamHI but not byHind III andEcoRI. The plasmid DNA from the remaining three strains was cleaved by all three restriction enzymes used.

ISSN:0266-8254    

DOI:10.1111/j.1472-765X.1994.tb00940.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

Mention of trade name, proprietary product or specific equipment is necessary to report factually on available data: however, the USDA neither guarantees nor warrants the standard of the product, and the use of the name by USDA implies no approval to the exclusion of others that may be suitable.The relative negative surface charge and hydrophobicity of four bacterial strains were evaluated by gravity flow and spin column methods. There was no significant difference between the two methods, indicating that spin column chromatography is an acceptable alternative method of determining cell surface charge or hydrophobicity. Six strains ofListeria monocytogeneswhich exhibited rough colony appearance were evaluated for surface charge and hydrophobicity and their ability to contaminate beef muscle tissue. With one exception, all of the rough strains exhibited greater net negative surface charge and reduced ability to contaminate beef during the initial stages of attachment. Since greater net negative cell surface charge has been positively correlated to attachment to beef tissue surfaces, the reduction in attachment exhibited by the rough strains was interpreted as an indication that attachment to beef tissue cannot be solely explained by cell surface charge.

ISSN:0266-8254    

DOI:10.1111/j.1472-765X.1994.tb00941.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

Escherichia coliisolated from six calves, in two groups of three which were managed differently and which received no antibiotics, were differentiated into strains on the basis of O serotype, biotype and resistance pattern. Keeping the calves in the maternal environment for 10, rather than 4 d, was associated with a delay in the time taken for strains ofE. coliresistant to antibacterial agents to outnumber, in the faeces, those that were sensitive. These findings indicate that the prevalence of resistantE. colistrains in the intestinal microbiota reflect, in part, their prevalence in the environment and that their level may be influenced by the management of the animal.

ISSN:0266-8254    

DOI:10.1111/j.1472-765X.1994.tb00942.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

Antagonisms among members of nine phenons of halobacteria were detected by combining two methods based on the double layer technique. Inhibitory activities were not due to phages. The protein nature of the inhibitors indicated that they were halocins. With only one exception, all strains tested exhibited inhibitory activity against other halobacteria due to the production of halocins. A very wide range of activity spectra was detected and the numerical comparative analysis showed little grouping, due to the scarce similarities between them. This indicates that many different halocins are produced by this heterogeneous group of micro‐organisms. Our results show that halocin production should be considered as a practically general feature of halobacteri

ISSN:0266-8254    

DOI:10.1111/j.1472-765X.1994.tb00943.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

We have established 950 and 430 oligoclonal B‐lymphoblastoid cell lines (LCL) from two normal persons and eight autoimmune disease patients, respectively by using Epstein‐Barr virus (EBV)‐induced transformation. To re‐evaluate the EBV technique for production of human monoclonal antibodies (mAb) related to infectious disease, we screened these oligoclonal LCLs for antibodies against 31 bacterial strains systematically. A total of 74 cultures out of 1380 were reactive to a total of 18 strains out of 31. Among these, eight cultures showed 10‐3antibody (Ab) titers toPseudomonas aeruginosaserotypes C, E, F and I,Staphylococcus aureus, Serratia marcescens and Bacillus cereus.Ten cultures showed 10‐2Ab titers toPs. aeruginosaserotypes D, E, F and I,Ps. maltophilia, Staph, epidermidis, Klebsiella ozaenae, Ser. marcescensandB. subtilis.The results reveal the further possibilities for the EBV technique to produce various infectious disease‐relat

ISSN:0266-8254    

DOI:10.1111/j.1472-765X.1994.tb00944.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

A new moderately halophilicMicrococcussp. 4, isolated from salt‐pan water from India, produced extracellular amylase when cultivated aerobically in medium containing wheat bran, peptone, beef extract and sodium chloride. Other salts, such as sodium nitrate, potassium nitrate and sodium sulphate, were also found to be suitable for growth and enzyme production. Maximum amylase activity (1.2 IU ml‐1) was secreted in the presence of 1 mol 1‐1sodium chloride. The enzyme requires the presence of either sodium chloride, potassium chloride, sodium nitrate, sodium citrate or sodium acetate for its activity. Maximum activity was found in the presence of 1 mol 1‐1sodium chloride. The pH and temperature optima for enzyme activity were 7.5 and 50°C, resp

ISSN:0266-8254    

DOI:10.1111/j.1472-765X.1994.tb00945.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

microbiological quality of the water produced by 38 bottling plants in Greece between 1987 and 1992 is presented and discussed. The presence ofPseudomonasspp. is also considered.

ISSN:0266-8254    

DOI:10.1111/j.1472-765X.1994.tb00946.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

High β‐N‐acetylhexosaminidase (EC.3.2.1.52) activity was detected during autolysis ofPenicillium oxalicum. Purification of the enzyme to homogeneity yielded an enzyme with a molecular weight of 132 000 Da by gel filtration and 71 900 Da by SDS polyacrylamide gel electrophoresis, suggesting a dimeric structure. The enzyme is an acidic protein with a pl of 5.0. Optimal activity was at pH 4.0 and 40°C, with aKmof 0.80 mmol 1‐1forp‐nitrophenyl‐β‐N‐acetylglucosaminide and 1.03 mmol 1‐1forp‐nitrophenyl‐β‐N‐acetylgalactosaminide. TheKiwith the competitive inhibitor O‐(2‐acetamido‐2‐deoxy‐D‐glucopyranosylidene) amino‐N‐phenylcarbamate was 1 μmol 1‐1. Hg2+, Ag+and Fe3+were effective inhibitors. β‐N‐acetylhexosaminidase hydrolysed chitobiose, chitotriose, chitotetrose and chitopentose to monomer to an extent of 92, 74, 44 and 17% respectively in 40 min. This enzyme, in conjunction with a purified endochitinase fromP. oxalicum, hydrolysed a cell‐wall chitin fraction isolated from t

ISSN:0266-8254    

DOI:10.1111/j.1472-765X.1994.tb00947.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY