Triosephosphate isomerase deficiency: haemolytic anaemia, myopathy with altered mitochondria and mental retardation due to a new variant with accelerated enzyme catabolism and diminished specific activity.

A new triosephosphate isomerase (TPI) variant is described in an 8-year-old Turkish girl suffering from chronic haemolytic anaemia, myopathy and developmental retardation since early infancy. The enzyme activity profile revealed a generalized deficiency in erythrocytes, granulocytes, mononuclear blood cells, skeletal muscle tissue and cerebrospinal fluid. The concentration of enzyme substrate dihydroxyacetone phosphate was distinctly elevated.

Expression of specific genes in early mouse embryos blocked by cytochalasin.

Mouse embryos at the two cell stage derived from C57BL/6 × C3H/Aa F-females heterozygous at the X-linked phosphoglycerate kinase locus (Pgk-1) were cultured continuously in the presence of cytochalasin B or D. Further cleavage of the two cell embryos was thus prevented and the embryos became polyploid during culture. The onset of expression of the maternally inherited Pgk-1 gene and of the paternally inherited glucosephosphate isomerase (Gpi-1) gene was determined in these polyploid embryos by cellulose acetate gel electrophoresis of single embryos.

On the interaction of bovine seminal RNase with actin in vitro.

Ribonuclease from bovine seminal plasma (RNase BS) interacts with skeletal muscle actin in the following way: it binds to actin with an apparent binding constant of 9.2 X 10(4) M-1 in 0.1 M KCl, induces the polymerization of actin below the critical concentration in depolymerization buffer, accelerates the salt-induced polymerization of actin even at a molar ratio of RNase to actin lower than 1/100, and bundles F-actin filaments.

Sequential expression of maternally inherited phosphoglycerate kinase-1 in the early mouse embryo.

Enzyme activities of X-linked phosphoglycerate kinase (PGK-1) and autosomal glucose phosphate isomerase (GPI-1) were determined in intact mouse blastocysts and isolated inner cell masses (ICMs). Blastocysts were recovered from the uterus on day 4 of gestation and cultured overnight in vitro. ICMs were isolated by treatment with calcium ionophore A23187.

Expression of X-linked phosphoglycerate kinase in early mouse embryos homozygous at the Xce locus.

The expression of maternally derived X-chromosomal Pgk-1 alleles was investigated in oocytes and early embryos of mice carrying different alleles (Xcea, Xcec) of the X-chromosome controlling element (Xce) locus. Pgk-1 allelic expression was determined by measuring their gene products using Cellogel electrophoresis and a sensitive fluorimetric enzyme assay. In addition to the already existing mouse strain of the genotypes Pgk-1a Xcec and Pgk-1b Xcea, a new line was bred carrying the combination Pgk-1b Xcec.

Preferential expression of the maternally inherited X-linked phosphoglycerate kinase allele in human erythrocytes.

The stability of allelic gene expression of X-linked phosphoglycerate kinase was studied in seven carriers of a rare genetic variant named PGK München. The enzymatic activities in erythrocytes of five heterozygous females and three hemizygous males were determined repeatedly over a period of 10 years (1975-1984) and shown to remain constant. As the phosphoglycerate kinase activity is lower in cells expressing the PGK München allele, the ratio of the two cell types in all heterozygous females of the PGK München kindred could be calculated from the PGK activity and from the known allozyme activities in erythrocytes of homozygous wild type or hemizygous PGK München carriers.

Purification and properties of the phosphoglycerate mutase isozymes from the mouse.

The two homodimeric isozymes of phosphoglycerate mutase have been purified from murine kidney and muscle. No differences were observed in the Michaelis-Menten constant for the substrate 2-phospho-D-glycerate, in molecular weight, temperature and pH optima, when the purified isozymes were compared. The isozymes differ in their inhibition constants for phosphoenolpyruvate, in their Michaelis constants for 3-phospho-D-glycerate and 2,3-bisphospho-D-glycerate, their thermal and pH lability and in their sensitivity towards mercury ions.

Comparison of the two purified allozymes (1B and 1A) of X-linked phosphoglycerate kinase in the mouse.

The two allelic isozymes (wild-type 1B and the electrophoretic variant 1A) of mouse X-linked phosphoglycerate kinase (PGK-1) have been purified by affinity chromatography. The following properties were determined for both forms: molecular weight, specific activity, nucleotide specificity, Km values of the four substrates, Ki of the ATP-ribosyladipoyldihydrazo-Mg complex, turnover number, activation energy, pH and ionic strength dependence, thermostability, content of free sulfhydryl groups, and antibody cross-reactivity. With the exception of specific activity and thermostability, both allozymes appear to be identical in all properties.

The expression of X-linked phosphoglycerate kinase in the early mouse embryo.

During early mouse embryogenesis, the activity of X-chromosomally linked maternal and paternal phosphoglycerate kinase (PGK-1) alleles was determined using electrophoretic separation of their gene products and a sensitive fluorometric enzyme assay. In the embryos collected from females homozygous for PGK-1b mated with PGK-1a males and vice versa, the paternally derived allozyme was first detected after implantation on day 6. Expression of the maternally inherited allele was studied in embryos from females heterozygous for PGK-1b and PGK-1a.

A single amino acid substitution (Asp leads to Asn) in a phosphoglycerate kinase variant (PGK München) associated with enzyme deficiency.

The structural abnormality of the phosphoglycerate kinase variant, PGK München, associated with red cell enzyme deficiency and heat instability, was elucidated by a microscale peptide-mapping method. A single amino acid substitution, from aspartic acid in the normal enzyme to asparagine in the variant enzyme, was found. From the known amino acid sequence of normal human phosphoglycerate kinase, the substitution is in the aspartic acid residue located at 268th position from the NH2-terminal of the protein.

The isolation and characterization of the multiple forms of human skeletal muscle triosephosphate isomerase.

1. Human skeletal muscle triosephosphate isomeras (D-glyceraldehyde-3-phosphate ketol-isomerase, EC 5.3.

Characterization of a phosphoglycerate kinase deficiency variants not associated with hemolytic anemia.

The properties of a variant phosphoglycerate kinase (PGK) found in a large German clan were examined. The normal and variant enzymes, isolated by affinity chromatography, have the same molecular weight, specific activity, substrate affinity, and nearly identical pH-optima. Using immunoinactivation and immunodiffusion, the same specific activity for both forms was again determined.

Isolation of phosphoglycerate kinases by affinity chromatography.

A variety of Sepharose derivatives containing DL-O-phosphorylserine or adenosine nucleotides with different points of attachment, has been synthesized and tested for affinity to phosphoglycerate kinase. The most effective gels contained periodate-oxidized ATP or ADP bound via the ribose by hydrazone formation to adipoyl-dihydrazo-Sepharose. The effect of pH, magnesium and buffer ions on the binding capacity of the ATP derivative of Sepharose has been examined.

Hereditary deficiency of phosphoglycerate kinase: a new variant in erythrocytes and leucocytes, not associated with haemolytic anaemia.

An X-chromosome linked phosphoglycerate kinase deficiency in erythrocytes and leucocytes was discovered in a large German kindred. Seven males of two generations were found to have only 21% of the normal enzyme activity in their erythrocytes, and twelve females of three generations showed various degrees of this defect. The differences in the expression of the deficiency in heterozygote females are explained by the Lyon hypothesis.

Linkage between phosphoglycerate kinase and Xg in a large German kindred.

In a family with an extremely rare PGK variant, linkage with Xg was investigated. The analysis suggested that linkage might prove measurable. The estimate of the recombination fraction was 0.