Relationship of Porphobilinogen Deaminase Activity to Chlorophyll Content and Fruit Development in `Heinz 1350' Tomato

Chlorophyll a and b contents were determined in developing tomato fruit (Lycopersicon esculentum Mill. `Heinz 1350') at 5-day increments from 10 or 15 days past anthesis to fulIy ripe (55 to 60 days). When presented on a whole-fruit basis, chlorophyll a and b contents increased from 15 days past anthesis to 35 days and then decreased to zero at 55 days. Porphobilinogen (EC 4.2.1.24; PBG) deaminase activity was measured in extracts from the fruit, and changes in PBG deaminase activity correlated with changes in chlorophyll and protein contents with respect to fruit age. Partial characterization of tomato PBG deaminase enzyme showed similarities to PBG deaminase enzymes isolated from other sources.

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Relationship of porphobilinogen deaminase activity to chlorophyll content and development of 'Heinz 1350' tomato fruit

10.31274/rtd-180813-8958 ◽

1984 ◽

Author(s):

Robert Waring McMahon

Keyword(s):

Chlorophyll Content ◽

Tomato Fruit ◽

Porphobilinogen Deaminase ◽

Relationship Of

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Reduced 5'-Methylthioadenosine Nucleosidase and 5-Methylthioribose Activities and Ethylene Biosynthesis in Nonripening Tomato Mutants `Rin' and `Nor' Relative to Ripening Tomato `Rutgers'

HortScience ◽

10.21273/hortsci.31.4.687f ◽

1996 ◽

Vol 31 (4) ◽

pp. 687f-688

Author(s):

Chunlin Xiao ◽

Mosbah M. Kushad

Keyword(s):

Fruit Development ◽

Tomato Fruit ◽

Maximum Level ◽

Ethylene Biosynthesis ◽

Fruit Growth ◽

Ethylene Synthesis ◽

Fruit Maturity ◽

Growth Development ◽

Relationship Of

5'-methylthioadenosine (MTA) nucleosidase (EC.2.2.2.28) and 5-methylthioribose (MTR) kinase (EC.2.7.1.100) activities were evaluated in `rin', `nor', and `Rutgers' tomato fruit during development and ripening. Changes in the activities of these enzymes were compared to ethylene biosynthesis. MTA nucleosidase and MTR kinase activities in `rin' and `nor' were ≈30% and 22%, respectively, lower than `Rutgers' during the first 2 weeks of fruit development. In `Rutgers', activities of these enzymes declined sharply until fruit maturity. Shortly before climacteric rise in ethylene synthesis, MTA nucleosidase, and MTR kinase activities increased, reaching a maximum level before peak ethylene synthesis then declined when fruit started to approach senescence. Whereas, `rin' and `nor' mutants exhibited no climacteric rise in ethylene synthesis and no change in MTA nucleosidase or MTR kinase activities, following their decline after 2 weeks of growth. A rapid increase in ethylene synthesis was observed when mature green `rin' and `nor' fruit were wounded. This increase in ethylene was paralleled by an increase in MTA nucleosidase and MTR kinase activities. However, increase in wound ethylene, MTA nucleosidase, and MTR kinase activities in `rin' and `nor' was ≈40% less than what we had previously reported in `Rutgers'. Relationship of MTA and MTR kinase activities to fruit growth, development, ripening, and natural and wound ethylene biosynthesis will be described.

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Fractionation and partial characterization of cell walls from normal and non-ripening mutant tomato fruit

Physiologia Plantarum ◽

10.1111/j.1399-3054.1984.tb05918.x ◽

1984 ◽

Vol 62 (1) ◽

pp. 25-32 ◽

Cited By ~ 74

Author(s):

Kenneth C. Gross

Keyword(s):

Cell Walls ◽

Tomato Fruit ◽

Partial Characterization

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Purification and Partial Characterization of a Protease from Tomato (Lycopersicon esculentum Mill)

Pakistan Journal of Biological Sciences ◽

10.3923/pjbs.1999.955.959 ◽

1999 ◽

Vol 2 (3) ◽

pp. 955-959

Author(s):

M.R. Karim ◽

M.A. Islam . ◽

N. Absar . ◽

F. Hashinaga .

Keyword(s):

Lycopersicon Esculentum ◽

Partial Characterization ◽

Lycopersicon Esculentum Mill

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Characterization of Glutamate-1-Semialdehyde Aminotransferase and Its Activity Throughout Tomato Fruit Development and Ripening

HortScience ◽

10.21273/hortsci.33.3.489a ◽

1998 ◽

Vol 33 (3) ◽

pp. 489a-489

Author(s):

Richard E. Finger ◽

David J. Hannapel ◽

Richard J. Gladon

Keyword(s):

Fruit Development ◽

Chlorophyll Biosynthesis ◽

Tomato Fruit ◽

Chlorophyll Concentration ◽

Maximum Velocity ◽

Primary Objective ◽

Fruit Development And Ripening ◽

Key Enzyme ◽

Secondary Objective

Glutamate-1-semialdehyde aminotransferase (GSAT) is a key enzyme in the regulation of chlorophyll biosynthesis and a plausible site to regulate chlorophyll loss during fruit development via a decrease in its activity. The primary objective of this research was to characterize GSAT from tomato fruit by varying substrate concentration and pH and to measure GSAT in various organs of the tomato plant. A secondary objective was to measure GSAT activity and chlorophyll concentration at 5-day intervals from 10 d to 60 d postanthesis during tomato fruit development and ripening. An optimum pH of 7.0 was found, and a maximum velocity (Vmax) of 2.3 nmol·g–1 of tissue and a Km of 119 mmol·L–1 were calculated for GSAT. Activity among organs was greatest at 3.84 nmol·g–1 tissue in leaves of 4-week-old seedlings, 1.67 nmol·g–1 tissue in fruits 15 days postanthesis, and below 0.70 nmol·g–1 tissue in roots, stems, and overripe fruits (65 d postanthesis). During fruit development, GSAT activity was greatest at 10 d postanthesis and declined to day 25. Activity increased from day 25 to a peak at day 40 and then decreased again during ripening to 60 d postanthesis. Total chlorophyll and chlorophyll a concentrations in tomato fruit declined throughout development and ripening with the greatest decrease between 10 d and 25 d postanthesis. Thus, GSAT activity may contribute to the control of chlorophyll concentration in tomato fruit from 10 to 25 d postanthesis when chlorophyll loss mirrors the decline in GSAT activity.

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Regulation of gene expression by ethylene during Lycopersicon esculentum (tomato) fruit development.

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.84.9.2793 ◽

1987 ◽

Vol 84 (9) ◽

pp. 2793-2797 ◽

Cited By ~ 166

Author(s):

J. E. Lincoln ◽

S. Cordes ◽

E. Read ◽

R. L. Fischer

Keyword(s):

Gene Expression ◽

Lycopersicon Esculentum ◽

Fruit Development ◽

Tomato Fruit ◽

Regulation Of Gene Expression

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Relationship of the Sweetpotato Whitefly to a New Tomato Fruit Disorder in Florida

HortScience ◽

10.21273/hortsci.25.12.1618 ◽

1990 ◽

Vol 25 (12) ◽

pp. 1618-1620 ◽

Cited By ~ 62

Author(s):

D.J. Schuster ◽

T.F. Mueller ◽

J.B. Kring ◽

J.F. Price

Keyword(s):

Lycopersicon Esculentum ◽

Bemisia Tabaci ◽

Tomato Fruit ◽

Sweetpotato Whitefly ◽

Field Cage ◽

Tomato Plants ◽

White Tissue ◽

Relationship Of

A new disorder of fruit has been observed on tomato (Lycopersicon esculentum Mill.) in Florida. The disorder, termed irregular ripening, was associated with field populations of the sweetpotato whitefly, Bemisia tabaci (Gennadius) and is characterized by incomplete ripening of longitudinal sections of fruit. An increase in internal white tissue also was associated with whitefly populations. In field cage studies, fruit on tomato plants not infested with the sweetpotato whitefly exhibited slight or no irregular ripening, whereas fruit from infested plants did. Fruit from plants on which a whitefly infestation had been controlled before the appearance of external symptoms exhibited reduced symptoms compared to fruit from plants on which an infestation was uncontrolled.

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