Unique Behavior of Bacterially Expressed Rat Carnitine Palmitoyltransferase 2 and Its Catalytic Activity

Mammalian type 2 carnitine parmitoyltransferase (EC 2.3.1.21), abbreviated as CPT2, is an enzyme involved in the translocation of fatty acid into the mitochondrial matrix space, and catalyzes the reaction acylcarnitine + CoA = acyl-CoA + carnitine. When rat CPT2 was expressed in Escherichia coli, its behavior was dependent on the presence or absence of i) its mitochondrial localization sequence and ii) a short amino acid sequence thought to anchor it to the mitochondrial inner membrane: CPT2 containing both sequences behaved as a hydrophobic protein, while recombinant CPT2 lacking both regions behaved as a water soluble protein; if only one region was present, the resultant proteins were observed in both fractions. Because relatively few protein species could be obtained from bacterial lysates as insoluble pellets under the experimental conditions used, selective enrichment of recombinant CPT2 protein containing both hydrophobic sequences was easily achieved. Furthermore, when CPT2 enriched in insoluble fraction was resuspended in an appropriate medium, it showed catalytic activity typical of CPT2: it was completely suppressed by the CPT2 inhibitor, ST1326, but not by the CPT1 inhibitor, malonyl-CoA. Therefore, we conclude that the bacterial expression system is an effective tool for characterization studies of mammalian CPT2.

Characteristics of adult scald burn patients-a single center study in western Kanagawa Prefecture

Burns sustained in bathtubs are a social and medical problem in Japan, especially among the elderly. Between October 2003 and March 2009, 22 adult scald burn patients (men, 17; average age, 65.3 ± 21.2 years) were transferred to Tokai University. In this study, we investigated the characteristics of these patients, and compared clinical parameters among patients with burns sustained in a bathtub (n = 10) and those with burns sustained due to other causes (n = 12). The average percentage total body surface area (%TBSA), dermal and deep burn area, and abbreviated burn severity index (ABSI) were 27.6 ± 23.8, 19.9 ± 20.5%, 7.8 ± 13.1%, and 7.7 ± 3.1, respectively. All patients in the bathtub burn group were elderly, 6 developed internal diseases, 3 had alcohol-related burns, and 4 died. Additionally, their %TBSA and ABSI were higher than those of the non-bathtub burn group patients. Burns sustained in bathtubs were more severe than those sustained due to other causes. The bathtub-related burn patients were elderly, and their burns were extensive and deep; hence, they were at a higher risk of developing internal diseases. Thus, introduction of safer bathing styles and bath systems will decrease incidences of bathtub-related burns.