Spirulina DNA sequence

[milpol]

Hi,
I need to know if there are DNA markers for Spirulina platensis or S. maxima. Where can I find information on the molecular sequence of these two species?
thanks

[danfive]

Try NCBI/Genebank: You can search http://www.ncbi.nlm.nih.gov/sites/gquery all databases for spirulina plantensis. Below the search bar a list of databases will display the number of hits for each database. Try Genome, EST (expressed sequence tags)

[milpol]

Thanks for the advice, i will try.

By the way, I have another question.
I have to determinate Spirulina protein content on fresh material. I am trying Lowry method, but it gave me some problems.
I use the method on fresh samples and afterwards I do a correction of the data on the basis of the relative humidity of my samples, which I obtain by difference between fresh and dry wheight.
This is the first time I determine protein by this method and I need some help. Somewhere in the protocol I dilute the samples up to 50 ml. When I calculate the protein content at the end of the experiment, do I have to take in account this dilution or I have to consider it as already counted in the protocol?

For example if I have these value from my curve
y = 1,1878x + 0,0057
R2 = 0,9778
and I have the following absorbance data:
0,269
0,229
0,207
in samples of respectively
518,8 mg
524,2 mg
514,2 mg
with humidity correction I obtain a teorical dry weigth of
25,9 mg
26,2 mg
25,7 mg
applying the formula (ABS-0.0057) / 1.1878 I obtain mg proteins/ml??? (or microliter??)
0,222
0,189
0,170????
considering that I had to dilute the samples twice of its initial volume, I multiplicated for 2.
Now the protein in my samples are
0,445 mg/ml
0,377
0,340
If I count the dilution to 50 ml during the protocol realization I have a %protein in my fresh material of
4,29
3,60
3,31
and if I consider my inferred dry weigth is
85,74
72,00
66,19
Which I consider too low in the fist option and too high in the second one.
Thanks in advance




Thanks in advance
Milena

[danfive]

Originally Posted by milpol

By the way, I have another question.
I have to determinate Spirulina protein content on fresh material. I am trying Lowry method, but it gave me some problems.
I use the method on fresh samples and afterwards I do a correction of the data on the basis of the relative humidity of my samples, which I obtain by difference between fresh and dry wheight.
This is the first time I determine protein by this method and I need some help. Somewhere in the protocol I dilute the samples up to 50 ml. When I calculate the protein content at the end of the experiment, do I have to take in account this dilution or I have to consider it as already counted in the protocol?

If Lowry isn't working, try BCA Microassay --> http://www.piercenet.com/products/br...fldID=02020102

I've measured the Calcium oxalate per gram dry weight in plant leaves, but never protein content. So I'm kinda guessing, that you want to determine protein content on fresh samples, then the relative humidity after getting dry weights on samples, separately. Those are very simple in two steps.

I you then want to extrapolate what the protein content equals in dry weight, as in 20% sample's dry weight is protein, then you extrapolate from your previous data.
For example 50mg/ml of 1g fresh samples is 50mg protein/g fresh sample (if your sample is homogenized in 1ml). And that equals 50mg protein/0.5g dry weight samples (assuming that 1g fresh will weigh 0.5g dry).