Kinase, in vitro: 

An enzyme-substrate reaction that occurs in non-living experimental conditions such as a test tube. For example, a purified enzyme is reacted with a substrate protein or mixture of proteins or peptides.

P38A S51-p
P38B S51-p
 Putative in vivo kinases: 

An enzyme-substrate reaction that occurs within living cells; includes cultured cells, ex vivo samples, and intact organisms. In the case of kinases, the large number of protein kinases in intact cells makes exact identification of the responsible kinase challenging.

P38A S51-p
P38B S51-p
Regulatory protein:
MKK6 S51-p
ATP S51-p
bafilomycin_A S51-p
CCCP S51-p
EBSS S51-p
EGF S51-p
IL-6 S51-p
JNK_inhibitor_VIII S51-p
LPS S51-p
MG132 K222-ub
MLN8054 S62-p
SB202190 S51-p
SB203580 S51-p
siRNA S51-p
taxol S62-p
thapsigargin S51-p
U0126 S51-p