scholarly journals Isolation and Characterization of Micromonospora Phage ΦHAU8 and Development into a Phasmid

2004 ◽  
Vol 70 (7) ◽  
pp. 3893-3897 ◽  
Author(s):  
Xiaohua Li ◽  
Xiufen Zhou ◽  
Zixin Deng

ABSTRACT ΦHAU8, a temperate Micromonospora phage, which is capable of infecting Micromonospora sp. strains 40027 and A-M-01, was isolated. The ΦHAU8 virion has a polyhedral head and a flexible tail and has a small genome (ca. 42.5 kb) with double-stranded DNA and cohesive ends. ΦHAU8 was most stable at 4°C in Difco nutrient broth within a pH range of 6 to 12. ΦHAU8 plaque formation on Micromonospora sp. strain 40027 was optimal with 32 mM Ca2+ and 30 mM Mg2+. A lysogen, LXH8, was isolated from turbid plaques, and a phasmid derivative that functions as a λ cosmid vector in Escherichia coli and as a phage in Micromonospora sp. strain 40027 was constructed. Pulsed-field gel electrophoresis of AseI-digested total DNA showed that ΦHAU8 DNA integrates into the 500-kb AseI fragment of Micromonospora sp. strain 40027.

1974 ◽  
Vol 31 (01) ◽  
pp. 072-085 ◽  
Author(s):  
M Kopitar ◽  
M Stegnar ◽  
B Accetto ◽  
D Lebez

SummaryPlasminogen activator was isolated from disrupted pig leucocytes by the aid of DEAE chromatography, gel filtration on Sephadex G-100 and final purification on CM cellulose, or by preparative gel electrophoresis.Isolated plasminogen activator corresponds No. 3 band of the starting sample of leucocyte cells (that is composed from 10 gel electrophoretic bands).pH optimum was found to be in pH range 8.0–8.5 and the highest pH stability is between pH range 5.0–8.0.Inhibition studies of isolated plasminogen activator were performed with EACA, AMCHA, PAMBA and Trasylol, using Anson and Astrup method. By Astrup method 100% inhibition was found with EACA and Trasylol and 30% with AMCHA. PAMBA gave 60% inhibition already at concentration 10–3 M/ml. Molecular weight of plasminogen activator was determined by gel filtration on Sephadex G-100. The value obtained from 4 different samples was found to be 28000–30500.


2002 ◽  
Vol 64 (3) ◽  
pp. 237-243 ◽  
Author(s):  
Yoshihisa WAKITA ◽  
Akira SHIMIZU ◽  
Václav HÁJEK ◽  
Junichi KAWANO ◽  
Kenji YAMASHITA

1994 ◽  
Vol 113 (1) ◽  
pp. 75-81 ◽  
Author(s):  
F. M. Khambaty ◽  
R. W. Bennett ◽  
D. B. Shah

SUMMARYAn outbreak of food intoxication involving over 265 cases in western United States occurred in October 1991.Staphylococcus intermediuswas implicated as the aetiologic agent. Representative outbreak isolates (five clinical and ten from foods) produced type A enterotoxin. DNA fragments generated by four restriction endonucleases and analysed by pulsed-field gel electrophoresis (PFGE) provided definitive evidence that all isolates from nine different counties in California and Nevada were derived from a single strain. The PFGE pattern of these outbreak isolates was distinct from those of a heterogeneous collection of sevenS. intermediusstrains of veterinary origin and five unrelatedS. aureuslaboratory strains. The data show a significant PFGE pattern heterogeneity not only among members of differentStaphylococcusspecies but also within members of the same species and even the same enterotoxin type. The results indicate that PFGE is a valuable strain-specific discriminator for the epidemiological characterization ofS. intermedius. To our knowledge, this represents the first documented foodborne outbreak caused byS. intermedius. These findings suggest that the presence ofS. intermediusand other species such asS. hyicusin food should be reason for concern.


1998 ◽  
Vol 36 (9) ◽  
pp. 2730-2731 ◽  
Author(s):  
Ge Wang ◽  
Qin Jiang ◽  
Diane E. Taylor

Clarithromycin-susceptible and clarithromycin-resistantHelicobacter pylori isolates from the same patient were investigated for the mode of development and mechanism of clarithromycin resistance. The clarithromycin-resistant strain UA1182 harbors homozygous A-to-G mutations at position 2143 in both copies of the 23S rRNA gene and has a phenotype of resistance to clarithromycin and clindamycin but no significant resistance to streptogramin B. Pulsed-field gel electrophoresis patterns of NruI- andNotI-digested genomic DNA from the Clas and Clar isolates demonstrated that they are genetically distinct, suggesting that the development of clarithromycin resistance is not from the mutation of the existing Clas strain but from a completely new strain.


2021 ◽  
Author(s):  
Bibiana Martins Barasuol ◽  
Juliana Felipetto Cargnelutti ◽  
Luis Antônio Sangioni ◽  
Daniela Isabel Brayer Pereira ◽  
Ana Paula Muterle Varela ◽  
...  

Abstract Bovine mastitis is an important disease of dairy cows, and Staphylococcus aureus is the etiologic agent most prevalent among the microorganisms. Mastitis caused by S. aureus present low cure rate with antimicrobials treatment and low vaccines efficacy. Bacteriophages or phages have been considered as an alternative for treating this disease. This study, we isolated and characterized two new S. aureus phages, namely B_UFSM4 and B_UFSM5, from bovine milk of cows with mastitis. The adsorptions rates were 10–20 min for B_UFSM4 and 20–30 min for B_UFSM5. Phages activities were relatively stable at pH 3–11; however, at temperatures of 50 °C-60ºC-70ºC/60 min, the phages were completely inactivated. These viruses presented infectivity in various bacteria isolated from bovine mastitis, where the lytic activity of phages B_UFSM4 and B_UFSM5 were 34.2%(13/38) and 42.1%(16/38), respectively, including isolates from S. aureus, Pseudomonas aeruginosa, Staphylococcus sciuri, and Rothia terrae. The complete genomes of B_UFSM4 and B_UFSM5 have 41.396 bp and 41.829 bp, with GC-content 33.97% and 33.98%, respectively. Both phages comprise 61 putative ORFs. The viruses have double stranded DNA and linear architecture. Phylogenic similarity was observed by proteome with Staphylococcus prophage phiPV83 (45,536 nt), Staphylococcus phage CN125 (44,492 nt) and Staphylococcus phage JS01 (43,458 nt). Based on the morphology, the phages belong to Siphoviridae family, presenting icosahedral head with a long tail, Caudovirales order and Biseptimavirus genus. Thus, two S. aureus phages (B_UFSM4 and B_UFSM5) were isolated and characterized, and these phages can be used as therapeutic or prophylactic candidates against S. aureus infections in cattle mastitis.


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