Monoclonal antibodies to the alternative oxidase of higher plant mitochondria

Journal Article · Sat Apr 01 00:00:00 EST 1989 · Plant Physiology; (USA)

DOI:https://doi.org/10.1104/pp.89.4.1311· OSTI ID:6651210

Elthon, T E; Nickels, R L; McIntosh, L ^[1]

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1. Michigan State Univ., East Lansing (USA)

The higher plant mitochondrial electron transport chain contains, in addition to the cytochrome chain which terminates with cytochrome oxidase, an alternative pathway that terminates with an alternative oxidase. The alternative oxidase of Sauromatum guttatum Schott has recently been identified as a cluster of proteins with apparent M{sub r} of 37, 36, and 35 kilodaltons (kD). Monoclonal antibodies have now been prepared to these proteins and designated as AOA (binding all three proteins of the alternative oxidase cluster), AOU (binding the upper or 37 kD protein), and AOL (binding the lower or 36 and 35 kD proteins). All three antibodies bind to their respective alternative oxidase proteins whether the proteins are in their native or denatured states. AOA and AOU inhibit alternative oxidase activity around 49%, whereas AOL inhibits activity only 14%. When coupled individually to Sepharose 4B, all three monoclonal resins were capable of retaining the entire cluster of alternative oxidase proteins, suggesting that these proteins are physically associated in some manner. The monoclonals were capable of binding similar mitochondrial proteins in a number of thermogenic and nonthermogenic species, indicating that they will be useful in characterizing and purifying the alternative oxidase of different systems. The ability of the monoclonal-Sepharose 4B resins to retain the cluster of previously identified alternative oxidase proteins, along with the inhibition of alternative oxidase activity by these monoclonals, supports the role of these proteins in constituting the alternative oxidase.

• DOE Contract Number: AC02-76ER01338
• OSTI ID: 6651210
• Journal Information: Plant Physiology; (USA), Vol. 89:4; ISSN 0032-0889
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
MONOCLONAL ANTIBODIES
BIOCHEMICAL REACTION KINETICS
OXIDOREDUCTASES
ENZYME ACTIVITY
BIOLOGICAL PATHWAYS
ELECTRON TRANSFER
IMMUNOASSAY
LILIOPSIDA
MEMBRANE TRANSPORT
MITOCHONDRIA
ANTIBODIES
BIOASSAY
CELL CONSTITUENTS
ENZYMES
KINETICS
MAGNOLIOPHYTA
ORGANOIDS
PLANTS
REACTION KINETICS
550200* - Biochemistry