Angiosperms need light to synthesize chlorophyll, but lotus (Nelumbo nucifera Gaertn.) embryo was suspected to have the ability to form chlorophyll in the dark because lotus embryo can turn into green under the covera...Angiosperms need light to synthesize chlorophyll, but lotus (Nelumbo nucifera Gaertn.) embryo was suspected to have the ability to form chlorophyll in the dark because lotus embryo can turn into green under the coverage of four layers of integuments (cotyledon, seed coat, pericarp, lotus pod) which were thought impossible for light to pass through. The authors excluded this possibility based on two experimental results: First, enclosing the young lotus pod with aluminium foil, the growth of louts embryo continued, but the chlorophyll formation was seriously inhibited. A lot of protochlorophyllide, chlorophyll precursor, were accumulated, most of which were combined with LPOR (light dependent protochlorophyllide oxidoreductase). Second, DPOR (dark or light-independent protochlorophyllide oxidoreductase) was the enzyme necessary for chlorophyll synthesis in the dark. The genes encoding DPOR were conservative in many species, but no homologues could be found in lotus genome. Taken together, authers' results clearly demonstrated that lotus embryo synthesizes chlorophyll only through the light-dependent pathway.展开更多
The interactions of chlorogenic acid （CA）, neochlorogenic acid （NCA） and cryptochlorogenic acid （CCA） with lysozyme （LYSO） were investigated in physiological buffer by fluorescence spectroscopy. The mechanism ...The interactions of chlorogenic acid （CA）, neochlorogenic acid （NCA） and cryptochlorogenic acid （CCA） with lysozyme （LYSO） were investigated in physiological buffer by fluorescence spectroscopy. The mechanism study indicated that CA, NCA and CCA could strongly quench the intrinsic fluorescence of LYSO through static quenching procedures with one binding site. Thermodynamic data show that the major force in the binding processes of CA to LYSO was hydrophobic interactions; for NCA, it was the hydrogen bonds and van der Waals forces, as for the CCA system, the mainly force is electrostatic force.展开更多
文摘Angiosperms need light to synthesize chlorophyll, but lotus (Nelumbo nucifera Gaertn.) embryo was suspected to have the ability to form chlorophyll in the dark because lotus embryo can turn into green under the coverage of four layers of integuments (cotyledon, seed coat, pericarp, lotus pod) which were thought impossible for light to pass through. The authors excluded this possibility based on two experimental results: First, enclosing the young lotus pod with aluminium foil, the growth of louts embryo continued, but the chlorophyll formation was seriously inhibited. A lot of protochlorophyllide, chlorophyll precursor, were accumulated, most of which were combined with LPOR (light dependent protochlorophyllide oxidoreductase). Second, DPOR (dark or light-independent protochlorophyllide oxidoreductase) was the enzyme necessary for chlorophyll synthesis in the dark. The genes encoding DPOR were conservative in many species, but no homologues could be found in lotus genome. Taken together, authers' results clearly demonstrated that lotus embryo synthesizes chlorophyll only through the light-dependent pathway.
文摘The interactions of chlorogenic acid （CA）, neochlorogenic acid （NCA） and cryptochlorogenic acid （CCA） with lysozyme （LYSO） were investigated in physiological buffer by fluorescence spectroscopy. The mechanism study indicated that CA, NCA and CCA could strongly quench the intrinsic fluorescence of LYSO through static quenching procedures with one binding site. Thermodynamic data show that the major force in the binding processes of CA to LYSO was hydrophobic interactions; for NCA, it was the hydrogen bonds and van der Waals forces, as for the CCA system, the mainly force is electrostatic force.
