Mycoplasma species

Bower, K., Djordjevic, S.R, Andronicos, N.M., and Ranson, M. (2003) Cell surface antigens of Mycoplasma species bovine group 7 bind to and activate plasminogen. Infect. Immunol. 71, 4823-4827. 

There are various methods for detecting Mycoplasma contamination of cell culture. A sensitive polymerase chain reaction test with broad specificity for Mycoplasma species is our method of choice (8). There are several products available for the eradication of Mycoplasma species from cell lines. The effectiveness of the treatment will depend on the cells and involves trail and error. This is because some cell lines are very sensitive to the chemicals used to eradicate Mycoplasma and may become static or die during treatment. 

Another specific application is the use of 0.1 pm syringe filters for the removal of mycoplasma in tissue culture work. They are capable of removing 99.99% of three common human mycoplasma species (M. hominis, M. salivarium and M. fermentans) and two common contaminants of fetal calf serum (M. arginini and Acholeplasma Laidlawii) [Hoffman, 1989]. 

Chloramphenicol is one of the older broad-spectrum antibiotics. It was introduced in 1948 and grew in popularity because of its high antimicrobial activity against a wide range of Gram-positive and Gram-negative bacteria, Rickettsiae, Chlamydia, and Mycoplasma species. It is particularly useful in infections caused by Salmonella typhi and Haemophilus influenzae. It is mainly bacteriostatic. It readily crosses tissue barriers and diffuses rapidly into nearly all tissues and body fluids. 

Position numbers are relative to the Escherichia coli 16S rDNA nucleotide sequence. The forward primer mollil and the reverse primer molli2a are used to detect Mycoplasma species. The forward primer mollil and the reverse primer molli2b are used to detect Acholeplasma species. Each set of primers are used separately. 

The PCR method that we have described is able to detect cell cultures containing contaminating mycoplasma species with great sensitivity (1.10 cfu/10 p.1) and seems to be more sensitive than the other techniques available. Also, PCR analysis can be performed from lyophilized cell cultures, which facilitates the transport of samples. Moreover, sample preparation is very simple and does not require any DNA extraction, so the results are obtained in 1 day. 

Pipet 0.25 mL of each capture antibody (one for each mycoplasma species) into two wells for each sample and into one well for each control, according to the information in Table 1. Repeat for three other species. Cover microtiter plate with aluminum foil and incubate for 2 h at 37°C. 

Most of the tests discussed above will detect all species of mycoplasma and closely related organisms, such as A. laidlawii. The table below shows a comparison of the methods described above. Isolation by culture will detect all species except for M. hyorhinis, which is noncultivable (14). The range of species which may be detected with the commercially available ELISA method described is much restricted since the ELISA assay, while allowing a positive identification of the contaminating mycoplasma species, detects only four species (M. orale, M. hyorhinis, M. arginini, and A. laidlawii). 

Currently, there are many examples of cell processing in the industrial environment using tangential flow filtration. To illustrate the breadth of microbial types which may be processed by this technology, we will discuss three applications which have been in routine operation under production conditions. The applications include cell/growth medium separations directly from fermentors (Escherichia coli and Mycoplasma species) and the concentration/washing of influenza virus used in the production of flu vaccines. 

Tilmicosin, Figure 1, is a new semisynthetic antibiotic derived from the macrolide antibiotic tylosin. The synthesis and antibacterial activity of tilmicosin have been described by Debono, et al. and Kirst, et al. (/-4). Tilmicosin has in vitro activity against a variety of Gram positive and Gram negative bacteria, as well as mycoplasma species. It is effective for treatment of bovine respiratory disease caused by Pasteurella haemolytica when administered as a single subcutaneous injection (5, 6). This paper describes the excretion, tissue residue pattern, and metabolism of tilmicosin when injected into cattle, and also gives comparative metabolism data from rats which were dosed orally. 

Lower respiratory tract disease may develop in neonates while hospitalized as a result of infection with organisms acquired perinatally from their mother s vaginal fiora. These can include the group B streptococcus, Mycoplasma species, and Ureaplasma urealyticum. 

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