PGM1 subtype polymorphism in 14 endogamous Dravidian-speaking populations of South India.

Red cell hemolysates from 1,004 persons belonging to 14 population groups drawn from four South Indian states, Andhra Pradesh, Tamil Nadu, Karnataka, and Kerala, were tested for PGM1 subtypes. The groups are characterized by a high frequency of phenotype 1+1+ (range 36.98-71.

Structure of a conjugative element in Streptococcus pneumoniae.

We have cloned and mapped a 69-kilobase (kb) region of the chromosome of Streptococcus pneumoniae DP1322, which carries the conjugative omega (cat-tet) insertion from S. pneumoniae BM6001. This element proved to be 65.

Cloning and physical characterization of chromosomal conjugative elements in streptococci.

We used a directed insertion method to introduce a nonreplicating vector plasmid into the large conjugative cat-tet element found in the chromosome of Streptococcus pneumoniae BM6001 and derivatives. To direct insertion preferentially to the conjugative element, we transferred it by conjugation to Streptococcus faecalis and then used DNA from this strain as a source of restriction nuclease fragments for ligation to digests of the vector pVA891, which can replicate in Escherichia coli but not in streptococci. This ligation mix was used to transform pneumococcal cells carrying the cat-tet element, with selection for the erythromycin resistance carried by pVA891.

Localization of competence-induced proteins in Streptococcus pneumoniae.

Intracellular locations of 11 proteins associated with the development of competence in Streptococcus pneumoniae were examined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis of subcellular fractions prepared from protoplasts. Controls showed that the competence-induced proteins were stable during the formation of protoplasts at 25 degrees C even though some had a half-life of only 8 min at 37 degrees C. Five competence-induced proteins p38, p27, p19.

A family study of dermatoglyphic traits in India: resolution of genetic and uterine environmental effects for palmar pattern ridge counts.

The inheritance of palmar pattern ridge counts for individual palmar areas, combined distal areas, and all ten areas combined was investigated in families belonging to two strictly endogamous Brahmin castes of peninsular India. Ridge count phenotypes were obtained by the method proposed by Malhotra et al. (1981a), however, zero observations (indicating patterns not circumscribed by triradii) were excluded from analysis.

Fate of DNA in eclipse complex during genetic transformation in Streptococcus pneumoniae.

Uptake of DNA and genetic recombination proceeded normally in competent Streptococcus pneumoniae despite inhibition of DNA replication by 6-(p-hydroxyphenylazo)-uracil. Immediately after a brief uptake period, 68% of donor DNA label was in eclipse complex form, and 22% was in low-molecular-weight products; by the completion of integration at 10 min, 23% was integrated into the chromosome, and the rest was lost from the cell. Throughout the process, less than 1% was found as free single strands.

Digital dermatoglyphics in some tribal populations of Andhra Pradesh, India.

An analysis of digital pattern types, ridge counts and pattern intensity index was made on samples from six tribal populations viz. Koya, Kolam, Rajgond, Chenchu, Pardhan and sugali. Bimanual, sexwise and inter-tribal comparisons were made for all the six tribes.

Determination of trace quantities of selenium by indirect atomic-absorption spectrophotometry.

The selenium(IV)-iodide interaction in acid medium, leading to the liberation of iodine, has been utilized for the indirect determination of selenium by atomic-absorption spectrophotometry (AAS). The iodine is extracted into benzene and subsequently reductively stripped into an aqueous solution of ascorbic acid. After extraction of the resulting iodide as tris(1,10-phenanthroline)cadmium(II) iodide into nitrobenzene, the cadmium content of the organic extract is determined by AAS.

Genetic studies on some tribes of the Telangana region, Andhra, Pradesh, India.

Phenotype distributions and gene frequencies of nine red cell enzyme systems and haemoglobin are presented for six tribal populations from the Telangana region of Andhra Pradesh. AEO, MN and Rh blood group data are presented for four of these tribes. The results have been compared with these from other Andhra Pradesh tribal Populations.

Fluorimetric determination of trace quantities of mercury as an ion-association complex with rhodamine 6G in the presence of iodide.

A procedure for the indirect fluorimetric determination of mercury(II) is described, based on selective extraction of the ion-association complex formed between triiodomercurate(II) and Rhodamine 6G and subsequent release of the fluorescent Rhodamine 6G. The calibration curve is linear up to 1 ppm of mercury(II). The few interferences are easily overcome.

Genetic studies on the Chenchu Tribe of Andhra Pradesh, India.

A total of almost 200 members of a tribal group, the Chenchu from the Mahabubnagar and Kurnool districts of Andhra Pradesh, have been tested for electrophoretic variation in a number of red cell enzyme systems. The former population has also been tested for ABO, MN and Rh blood group systems and for the serum proteins Hp, Tf and albumin. The most significant findings were the presence of the gene ry, and the occurrence of a polymorphism in PHI with the variant gene PHI5 having a gene frequency of 4%.

Spectrophotometric determination of tellurium in trace quantities by use of an ion-association complex.

The formation of an ion-association complex by the interaction of iodotellurate(IV) with cetyltrimethylammonium bromide is used as the basis of an extractive procedure to determine tellurium in the range 2.5-12.5 mug in a final aqueous phase volume of 20 ml.