Effect on epidermal cell of soybean protein-degraded products and structural determination of the root hair promoting peptide.
Peptide(s) produced from degraded soybean protein by an alkaline protease from Bacillus circulans HA12 (degraded soybean-meal products; DSP) increased the number of both the root hair cells (trichoblasts) and hairless cells (atrichoblasts) of Brassica rapa by about 4.4 times and 1.9 times, respectively. To identify the root hair-promoting peptide(s) in DSP, the origin protein of the root hair-promoting peptide(s) was identified as Kunitz trypsin inhibitor (KTI). The root hair-promoting peptide in the degraded products of KTI was purified and produced a signal of 1,198.2 Da with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) analysis. A search of the amino acid sequence of KTI located the peptide GGIRAAPTGNER, which had a molecular weight identical to 1,198.2 Da. The peptide GGIRAAPTGNER was chemically synthesized, and the synthetic peptide possessed root hair-promoting activity. Thus, it is concluded that this peptide in DSP is the foreign bioactive peptide promoting the differentiation of root hairs.
Matsumiya
Yoshiki
Y
Department of Bioscience and Technology, Faculty of Science and Engineering, Ritsumeikan University, Nojihigashi, Kusatsu, Shiga, Japan.
Sumiyoshi
Sayoko
S
Matsukura
Takuma
T
Kubo
Motoki
M
D000595:Amino Acid Sequence; D002850:Chromatography, Gel; D004591:Electrophoresis, Polyacrylamide Gel; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010455:Peptides / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D019441:Plant Epidermis / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D018517:Plant Roots / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D030262:Soybean Proteins / Q000737:chemistry / Q000378:metabolism*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D014360:Trypsin Inhibitor, Kunitz Soybean / Q000737:chemistry / Q000378:metabolism
D010455:Peptides; D030262:Soybean Proteins; D014360:Trypsin Inhibitor, Kunitz Soybean