what do you think of this gel ? - (Oct/30/2008 )
On the other hand, it is fine that at leas one negative control is OK! (compare with your previous PCR without DNA!). Most likely contamination is not in your PCR components, with the exception of BSA.
I suggest not to use BSA, it seems there might be something in it (smear in all PCRs with BSA). Also results with/without BSA are similar, you can get PCR product without it.
I am not sure about RNase A. It seems like completely inhibited the reaction, maybe EtOH precipitation before PCR can help.
Neg1 and Mix on the gel are the same sample (mix is the leftover of mastermix). One has a band, not the other. It is making me mad.
Help !!!!!!!
I suggest not to use BSA, it seems there might be something in it (smear in all PCRs with BSA). Also results with/without BSA are similar, you can get PCR product without it.
I am not sure about RNase A. It seems like completely inhibited the reaction, maybe EtOH precipitation before PCR can help.
Yes I agree, I'll try not to use BSA to limit smears. I have ordered DNase, filtered tips, PCR grade water and a new PCR kit. Le'ts see if things improve....
I heard Gibcos' Hyclone BSA batch was contaminated with mycoplasma a couple of months (years?) ago...Perhaps this might explain these events? I have also noted that proteins DO show up on agarose gels run for nucleic acids and have personally experienced protein smears in PCR product after a studen of mine addedd50 times more taq than needed (don't even go there). Best regards.