. 2006 Aug 18;34(17):4912–4924. doi: 10.1093/nar/gkl472

Table 4.

The periodic table of tandem mismatch (2 × 2 internal loop) enthalpy^a

Closing BP	Mismatch
	GA	AG	UU	GG	CA	CU	UC	CC	AC	AA
	AG	GA	UU	GG	AC	UC	CU	CC	CA	AA
GC	−31.0^c	−15.6^c	−14.4^b	−22.8	−10.3^b	−29.4^b	(−14.7)	(−14.7)	−8.6^b	−1.3^b
	−15.9^c					−12.4^b
	−28.4^c					−20.9
	−25.1
CG	−8.9^d	−12.7^d	−17.5^d	−22.8^d	−10.8^d	−0.6^d	−2.8^d	−1.8^d	−1.7^d	−4.2^d
	−16.5^g									−5.0^e
	−14.6									−4.6
UA	−13.4^c	−19.4	−6.7^b	2.7	9.1^b	3.3^b	9.5^b	(12.1)	(12.1)	14.7^b
AU	−17.9^c	−10.8	−12.2^b	−1.0	7.2^b	(7.4)	(7.4)	(7.4)	7.5^b	13.4^b
	−11.0^c
	−14.4
UG	−15.3^c	−18.7^f	(−8.5)	(−8.5)	(−8.5)	(−8.5)	(−8.5)	(−8.5)	(−8.5)	1.7^b
GU	−19.9^c	−16.1^f	(−19.6)	(−19.6)	(−19.6)	(−19.6)	(−19.6)	(−19.6)	(−19.6)	−23.2^f

^aBoldface numbers are averages of multiple measurements on the same internal loops and numbers in parentheses are predicted by average of the nearest numbers to the left and right. The enthalpies of reference helices were taken from Ref. (21).

The enthalpies (kcal/mol) are drawn from b, Ref. (76); c, Ref. (52); d, Ref. (55,77); e, Ref. (78); f, (79); g, Ref. (80).