Table 1.

Variation in pI in functionally classified groups of COGs. The table lists functional groups of COGs as defined in the COG website [22] along with the results of the Dunn Multiple Comparison test. R_i – mean rank for the group, R_t – mean rank for sample representing the complete distribution. Significant values are those where |R_t - R_i| > 467.35 which is calculated for α = 0.2

		Ri	Ri - Rt
Metabolism
C	Energy production and conversion	2563.72	276.96
E	Amino acid transport and metabolism	2792.99	47.69
F	Nucleotide transport and metabolism	2191.12	649.56
G	Carbohydrate transport and metabolism	2958.98	-118.3
H	Coenzyme metabolism	2736.4	104.28
I	Lipid metabolism	2587.87	252.81
Q	Secondary metabolism biosynthesis, transport and catabolism	2479.07	361.62
Information storage and processing
J	Translation, ribosomal structure and biogenesis	3399.31	-558.63
K	Transcription	2977.93	-137.25
L	DNA replication, recombination and repair	3530.56	-689.88
Cellular process
M	Cell Envelope biogenesis, Outer membrane	3287.13	-446.45
N	Cell motility and secretion	2722.08	118.6
O	Post translation modification, protein turnover, chaperones	2445.01	395.67
P	Inorganic ion transport and metabolism	3482.93	-642.25
T	Signal transduction mechanisms	2219.23	621.45
D	Cell devision and chromosome partitioning	2836.43	4.25
Poorly characterized
R	General function prediction only	3189.18	-348.5
S	Function unknown	2918.88	-78.2
		Rt = 2840.68