The suspensions, diluted to OD600=1 0 (which is equivalent to 1 X

The suspensions, diluted to OD600=1.0 (which is equivalent to 1 X107 CFU/ml) with

PBS, were used to infect cell lines with different multiplicity of infection (MOI). Cell lines and their culture Human cell lines THP-1 (TIB-202) and HeLa (CCL-2) were purchased from American Type Culture Collection (ATCC, Manassas, VA). THP-1 and HeLa cells were cultured in RPMI and Dulbecco’s modified Eagle’s medium (DMEM), respectively, with 10% FBS at 37°C in a humid chamber with 5% CO2. DNA manipulations Plasmids from E. coli were isolated using QIAprep Spin kit (Qiagen). Genomic DNA from mycoplasma was isolated using DNA isolation kit (Invitrogen). Primers for amplification of MG_207 gene and subsequent site directed mutagenesis were see more synthesized at the DNA core facility, The University ubiquitin-Proteasome system of Texas Health Science Center at San Antonio (UTHSCSA). The whole gene encoding MG207 was amplified by PCR using primers MG_207EX1 (5´-ACGCATATGCAAAACAAACTGATTAAGGTT-3´) and MG_207EX2 (5´-CAGTCGGATCCGTTAACTAACTTTTGAAGCTTG-3´) ITF2357 price and M. genitalium genomic DNA as template. This fragment

was cloned into pCR 2.1 to result in pMG207. The gene MG_207 has a TGA codon for tryptophan residue, which will be recognized as stop codon by E. coli, and this needed modification into TGG to express the gene in E. coli. To do this modification (point mutation), we used QuikChange Site-Directed Mutagenesis Kit (Stratagene) and primers MG_207M1 (5´-CAAAATGCTACTTTTTGGGTGGCAGGTAACAAC-3´) and MG_207M2 (5´-GTTGTTACCTGCCACCCAAAAAGTAGCATTTTG-3´). Plasmid pMG207 served as the template for point mutation. Subsequent to point mutation, the newly synthesized plasmid DNA (pMG207A) was transformed

into E. coli, plasmid isolated and the sequence of the insert region was verified to confirm the point mutation. The coding region of MG_207 from pMG207A was digested with NdeI and BamHI and the fragment cloned into similarly cut pET16b expression vector. This plasmid (pMG207EX) was transformed into much E. coli BL21 (DE3) strain to overexpress His10MG207 protein. Southern hybridization To reconfirm the insertion of transposon Tn4001 in MG_207, we performed Southern hybridization. Briefly, chromosomal DNA from M. genitalium G37 and TIM207 was cut with SpeI and separated in 1% agarose gels. The separated DNA fragments were transferred to Zeta probe membranes (Bio-Rad) by Southern blotting and crosslinked with UV. Prehybridization of the membranes was performed in a solution containing 50% formamide, 0.12 M Na2HPO4, 0.25 M NaCl, and 7% (wt/vol) sodium dodecyl sulfate (SDS) for 4 h. Hybridization of the membranes was done in the same solution with [α-32P]dCTP labeled probe DNA of MG_207 or gentamicin gene for overnight at 42°C. The membranes were washed at 42°C (each wash for 15 min with solutions A (2X SSC with 0.1% SDS), B (0.5X SSC with 0.1% SDS) and C (0.1X SSC with 0.1% SDS) for three times.

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