Preparation and properties of mitochondria from cowpea nodules.

نویسندگان

  • S Rawsthorne
  • T A Larue
چکیده

Mitochondria were isolated from nodules of cowpea (Vigna unguiculata (L). Walp.) and purified on a Percoll gradient. They were only slightly contaminated by bacteroids (an average of 3.5%), and had low lipoxygenase activity. Compared to mitochondria from hypocotyls the nodule mitochondria had similar O(2) uptake rates and respiratory control ratios. The ADP/O ratios for both preparations were 1.4 to 1.7 and 2.3 to 2.6 with succinate and malate, respectively. Whereas mitochondria isolated from etiolated cowpea hypocotyls had 14 to 18% of their respiration insensitive to KCN, the respiration of nodule mitochondria was completely inhibited by KCN. Enzyme activities of nodule mitochondria were similar to those found in hypocotyl mitochondria, except for NAD(+)-malic enzyme which was 12-fold lower in the mitochondria from nodules.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Metabolism under Microaerobic Conditions of Mitochondria from Cowpea Nodules.

A method is described for isolating mitochondria from nodules of cowpea (Vigna unguiculata [L.] Walp.) under completely anaerobic conditions. The mitochondria were immediately active when incubated aerobically with substrates, and their respiration rates were higher than mitochondria prepared in air. The mitochondria lacked fumarate reductase and were not inhibited by 5% CO(2). When incubated u...

متن کامل

Expression studies of superoxide dismutases in nodules and leaves of transgenic alfalfa reveal abundance of iron-containing isozymes, posttranslational regulation, and compensation of isozyme activities.

The composition of antioxidant enzymes, especially superoxide dismutase (SOD), was studied in one nontransgenic and three transgenic lines of nodulated alfalfa plants. Transgenic lines overproduced MnSOD in the mitochondria of nodules and leaves (line 1-10), MnSOD in the chloroplasts (line 4-6), and FeSOD in the chloroplasts (line 10-7). In nodules of line 10-7, the absence of transgene-encoded...

متن کامل

MODULATION OF MITOCHONDRIAL UPTAKE OF A DENOSINE BY NITROBENZYLTHIOINOSINE

In this study the uptake and metabolism of adenosine by mitochondria has been investigated. Incubation of CEM cells mitochondria preparation with [3H] -adenosine showed substantial uptake and metabolism of adenosine. Adenosine was both anabolized to AMP, ADP and ATP, and also catabolized to inosine. The highest concentration of metabolites in extracted mitochondria was due to AMP. The mito...

متن کامل

Phylogenetic diversity and cross-inoculation of indigenous isolated Bradyrhizobium from nodules of peanut in Liaoning province of China

Arachis hypogaea. L is a legume of economic importance, which is nodulated by Bradyrhizobium, a slow-growing bacteria. However there is no well characterization of this rhizobia in many areas of China. In the present study, cross-inoculation experiments were performed in cowpea and soybean. The isolated bacteria strains were characterized physiologyically, biochemically and id...

متن کامل

Molecular cloning of the cowpea leghemoglobin II gene and expression of its cDNA in Escherichia coli. Purification and characterization of the recombinant protein.

Cowpea (Vigna unguiculata) nodules contain three leghemoglobins (LbI, LbII, and LbIII) that are encoded by at least two genes. We have cloned and sequenced the gene that encodes for LbII (lbII), the most abundant Lb in cowpea nodules, using total DNA as the template for PCR. Primers were designed using the sequence of the soybean lbc gene. The lbII gene is 679 bp in length and codes for a predi...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:
  • Plant physiology

دوره 81 4  شماره 

صفحات  -

تاریخ انتشار 1986