Exchange of terminal portions of X- and Y-chromosomal short arms in human XY females.

Human Y(+) XX maleness has been shown to result from an abnormal terminal Xp-Yp interchange that can occur during paternal meiosis. To test whether human XY females are produced by the same mechanism, we followed the inheritance of paternal pseudoautosomal loci and Xp22.3-specific loci in two XY female patients.

Inactivation of lincosaminide antibiotics in Staphylococcus. Identification of lincosaminide O-nucleotidyltransferases and comparison of the corresponding resistance genes.

Resistance to lincomycin by inactivation has been detected in numerous clinical isolates of Staphylococcus; in crude extracts of Staphylococcus haemolyticus BM4610 and Staphylococcus aureus BM4611, inactivation of lincomycin and clindamycin requires the presence of a nucleoside 5'-triphosphate (ATP, GTP, CTP, or UTP) as nucleotidyl donor and Mg2+ as cofactor. The biochemical mechanism of lincosaminide inactivation was elucidated by determination of the structure of inactivated lincomycin and clindamycin by physicochemical techniques, including UV absorption spectrophotometry, 31P and 1H nuclear magnetic resonance, and periodate oxidation. In the two strains, inactivation of lincomycin gave rise to lincomycin 3-(5'-adenylate), whereas clindamycin was inactivated through its conversion to clindamycin 4-(5'-adenylate).