Swinging effect of salicylic acid on the accumulation of polyhydroxyalkanoic acid (PHA) in Pseudomonas aeruginosa BM114 synthesizing both MCLandSCL-PHA.
A bacterium, Pseudomonas aeruginosa BM114, capable of accumulating a blend of medium-chain-length (MCL)- and short-chain-length (SCL)-polyhydroxyalkanoic acid (PHA), was isolated. Salicylic acid (SA), without being metabolized, was found to specifically inhibit only the accumulation of MCL-PHA without affecting cell growth. An addition of 20 mM SA selectively inhibited the accumulation of MCL-PHA in decanoate-grown cells by 83% of the control content in one-step cultivation, where overall PHA accumulation was inhibited by only approximately11%. Typically, the molar monomerunit ratio of the PHA for 25 mM decanoate-grown cells changed from 46:4:25:25 (=[3-hydroxybutyrate]:[3-hydroxycaproate]: [3-hydroxyoctanoate]:[3-hydroxydecanoate]) at 0 mM SA (dry cell wt, 1.97 g/l; PHA content, 48.6 wt%) to 91:1:4:4 at 20 mM SA (dry cell wt, 1.85 g/l; PHA content, 43.2 wt%). Thus, the stimulation of SCL-PHA accumulation was observed. Growth of P. aeruginosa BM114 on undecanoic acid also produced a PHA blend composed of 47.4% P(3HB-co-3- hydroxyvalerate) and 52.6% P(3-hydroxyheptanoate-co-3- hydroxynonanoate-co-3-hydroxyundecanoate). Similar to the case of even-carboxylic acids, SA inhibited the accumulation of only MCL-PHA, but stimulated the accumulation of SCLPHA. For all medium-chain fatty acids tested, SA induced a stimulation of SCL-PHA accumulation in the BM114 strain. SA could thus be used to suppress only the formation of MCL-PHA in Pseudomonas spp. accumulating a blend of SCL-PHA and MCL-PHA.
Rho
Jong Kook
JK
Division of Applied Life Sciences (BK21), Graduate School, Gyeongsang National University, Jinju 660-701, Korea.
Choi
Mun Hwan
MH
Shim
Ji Hoon
JH
Lee
So-Young
SY
Woo
Myeong Ji
MJ
Ko
Bong-Sung
BS
Chi
Ki-Whan
KW
Yoon
Sung Chul
SC
D002210:Caprylates / Q000378:metabolism; D003651:Decanoates / Q000378:metabolism; D005227:Fatty Acids / Q000378:metabolism; D009682:Magnetic Resonance Spectroscopy; D054813:Polyhydroxyalkanoates / Q000096:biosynthesis* / Q000378:metabolism*; D011550:Pseudomonas aeruginosa / Q000187:drug effects* / Q000378:metabolism*; D020156:Salicylic Acid / Q000494:pharmacology*
D002210:Caprylates; D003651:Decanoates; D005227:Fatty Acids; D054813:Polyhydroxyalkanoates; C008776:pelargonic acid; D020156:Salicylic Acid