Table 3.

Quantification of the Relative Amount of Hsp21 in the Chloroplast Soluble Stroma in Heat‐Stressed Plants Compared to Control Plants

z	Sequence	L/H	L/H*0.71	%H	%H*1.2	Std. Err.	Fraction	Correlation	Intensity
	Stroma
2+	KVIDVQIQ	2.96	2.10	0.25	0.30	0.082	0.281	0.997	3 376
2+	NGVLFITIPK	2.33	1.65	0.30	0.36	0.061	0.665	0.997	39 490
2+	ISVEDNVLVIK	3.25	2.31	0.24	0.28	0.193	0.419	0.996	55 310
4+	APWDIKEEEHEIK	2.90	2.06	0.26	0.31	0.143	0.508	0.996	2 757
3+	APWDIKEEEHEIK	2.72	1.93	0.27	0.32	0.147	0.353	0.995	5 559
3+	ISVEDNVLVIKGEQK	2.43	1.72	0.29	0.35	0.136	0.181	0.996	14 130
3+	LTMDVSPFGLLDPLSPMR	2.48	1.76	0.29	0.35	0.085	0.625	0.996	15 490
2+	LTMDVSPFGLLDPLSPMR	2.34	1.66	0.30	0.36	0.069	0.878	0.998	110 500
3+	QMLDTMDRMFEDTMPVSGR	2.20	1.56	0.31	0.37	0.040	0.790	0.996	17 190
	Average	2.34
	Thylakoid membranes
2+	FDMPGLSK	0.17	0.12	0.85	1.02	2.219	0.413	0.953	458 000
2+	QMLDTMDR	0.03	0.02	0.97	1.17	0.028	0.247	0.980	6 954
2+	MFEDTMPVSGR	0.03	0.02	0.97	1.17	0.002	0.204	0.989	1 812 000
2+	ENSIDVVQQGQQK	0.02	0.02	0.98	1.17	0.000	0.709	0.995	1 269 000
2+	APWDIKEEEHEIK	0.05	0.04	0.95	1.14	0.081	0.061	0.997	61 230
4+	APWDIKEEEHEIK	0.02	0.01	0.98	1.18	0.005	0.243	0.996	61 840
3+	APWDIKEEEHEIK	0.02	0.01	0.98	1.18	0.089	0.068	0.969	180 500
3+	LTMDVSPFGLLDPLSPMR	0.03	0.02	0.97	1.17	0.004	0.613	0.995	972 200
2+	LTMDVSPFGLLDPLSPMR	0.03	0.02	0.97	1.17	0.003	0.273	0.998	3 780 000

The amount of protein in the thylakoid membrane in heat‐stressed plants compared to control plants is expressed as %H= H/L + H, based on the L/H‐ratio (Light (¹⁴N)/Heavy(¹⁵N)) calculated by the Mascot Distiller Toolbox software for at least 3 peptides as the sum of the signals from the heavy isotope divided by the sum of all signals of the light and heavy peptide.

SD_geo, parameter presented by the Mascot Distiller Quantitation Toolbox to estimate the average L/H‐ratios and should be >1.

Number of unique peptides identified by MS/MS and used to determine L/H‐ratio.

Mascot protein score.

Peptides of the Hsp21 protein were detected in the gel segment at approximately 25 kDa excised after electrophoretic separation of proteins in a 1:1 mixture of soluble stroma fraction from heat‐stressed ¹⁵N‐plants and control ¹⁴N‐plants. As a comparison, corresponding data for chloroplast thylakoid membranes are also listed. Apart from the values for L/H and %H, determined as described in Table 2, four quality parameters (Standard error, Fraction, Correlation and Intensity) are presented which are used by the Mascot Distiller Quantitation Toolbox software to decide which peptides to include. The peptides that are included in the final calculation of average L/H‐ratio for the protein are indicated in bold.