Systems analysis of ethanol production in the genetically engineered cyanobacterium Synechococcus sp. PCC 7002

Table 1 Phase I changes of primary metabolism comparing the Synechococcus 7002 producer to WT

Metabolite	Response ratio (Producer/WT)		T test significance
	Day 3	Day 7	Day 3	Day 7
	Log₂	Log₂	P < 0.05	P < 0.05
Alanine	−0.864	−1.083	1.0E−02	8.3E−05
Isoleucine	−0.725	−1.171	1.4E−03	3.0E−05
Valine	−0.677	−1.736	4.7E−03	5.8E−05
Glutamic acid	−0.506	−0.414	1.1E−02	8.2E−05
Glutamic acid, N-acetyl-	−0.681	−0.223	2.8E−06	1.9E−03
Glutamine (pyroglutamate, glutamate)^a	−0.480	−0.544	6.7E−04	1.2E−04
Succinate	−0.435	−0.624	3.0E−03	2.1E−06
Succinate semialdehyde	−0.763	−1.075	2.8E−07	9.8E−09
Glyceric acid	−1.739	−1.410	5.2E−05	5.7E−05
Glycerophosphoglycerol	−0.860	−0.900	1.2E−05	1.7E−07
Glycine	1.741	2.954	8.6E−07	1.1E−05
A231002	−0.474	−0.868	2.0E−03	7.8E−07
A300001	0.603	0.468	3.2E−03	1.8E−02

Log₂-transformed initial changes, i.e. response ratios of producer over wild type (WT), at low ethanol concentration (Fig. 1), were calculated and significance tested P < 0.05 using the t test (italics font: P < 0.0001)
^aPyroglutamic acid represents the sum of the glutamine, pyroglutamic and glutamic acid pool