University of Maryland Biotechnology Institute

About: University of Maryland Biotechnology Institute is a based out in . It is known for research contribution in the topics: Gene & Population. The organization has 1565 authors who have published 2458 publications receiving 171434 citations. The organization is also known as: UMBI.

Early Maturity in the Male Striped Bass, Morone saxatilis: Follicle-Stimulating Hormone and Luteinizing Hormone Gene Expression and Their Regulation by Gonadotropin-Releasing Hormone Analogue and Testosterone

Abstract: Striped bass are seasonal breeding fish, spawning once a year during the spring. All 3-yr-old males are sexually mature; however, 60–64% of the fish mature earlier as 1- or 2-yr-old animals. The endocrine basis underlying early maturity in 2-yr-old males was studied at the molecular level by monitoring changes in pituitary βFSH and βLH mRNA levels by ribonuclease protection assay, and correlating these changes to stages of testicular development. In maturing males, the mRNA levels of βFSH were elevated during early spermatogenesis, whereas βLH mRNA levels peaked during spermiation. The appearance of spermatozoa in the testis was associated with a decrease in βFSH mRNA and a rise in βLH mRNA abundance. Immature males had lower levels of βLH mRNA than maturing males, but there were no differences in βFSH mRNA levels between immature and maturing males. The regulation of gonadotropin gene expression in 2-yr-old males was studied by the chronic administration of GnRH analogue (GnRHa) and testosterone...

Chromium accumulation by two Streptomyces spp. isolated from riverine sediments.

Abstract: Strains designated R22 and R25, isolated from Sali River sediments, Argentina, were highly resistant to chromium. These strains were shown by 16S rRNA sequencing studies to be Streptomyces spp.; this affiliation was consistent with morphological and chemical characteristics. Growth of strains R22 and R25 in medium containing 100 mg l(-1) chromate was reduced by only 23% and 34%, respectively, compared with growth in medium without added chromium. Streptomyces sp. strains R22 and R25 both accumulated chromium with yields of 10.0 and 5.6 mg Cr g(-1) of dry weight, respectively, and a chromate concentration of 50 mg ml(-1). Cell fractionation studies with strain R22 showed that the great majority of the chromium were associated with the cell wall fraction. Streptomyces strains R22 and R25 may have applications in bioremediation of chromium contamination.