The abundance of cellular proteins is determined largely by the rate of transcription and translation coupled with the stability of individual proteins. Although we know a great deal about global transcript abundance, little is known about global protein stability. We present a highly parallel multiplexing strategy to monitor protein turnover on a global scale by coupling flow cytometry with mi...

1. When Escherichia coli was grown exponentially in a defined medium at 35 degrees , the rate of protein breakdown was initially rapid, but decreased to 0.6%/hr. after about 30min. The latter rate was maintained for at least 3.5hr. 2. The initial rapid rate may have been due to the presence of a small protein fraction (about 1%) that was degraded with a half-life of 13min. 3. The rate of protei...

Although bulk protein turnover has been measured with the use of stable isotope labeled tracers for over half a century, it is only recently that the same approach has become applicable to the level of the proteome, permitting analysis of the turnover of many proteins instead of single proteins or an aggregated protein pool. The optimal experimental design for turnover studies is dependent on t...

This study was conducted to evaluate the effect of electron beam irradiation at doses of 250 and 500 kGy on the chemical composition and ruminal dry matter (DM) and neutral detergent fiber (NDF) degradability of wheat straw. Nylon bags of untreated or irradiated wheat straw were suspended in the rumen of three rams for up to 72 h, and resulting data were fitted to non-linear degradation model t...

The objective of this study was to investigate the effects of cut and irrigation water quality on chemical composition and in situ dry matter (DM), crude protein (CP) and neutral detergent fiber (NDF) degradability of alfalfa. Three fistulated Zel sheep (approximately 2 years old) were used in a complete randomized design to evaluate the in situ rumen degradability. Ruminal in...

This study was undertaken to determine whether the protein feeding pattern could induce chronic adaptation of protein turnover. After a 15-day adaptive period, elderly (68 yr) and young (26 yr) women received, for 14 days, a diet providing 200 KJ x kg fat-free mass (FFM)(-1) x day(-1), where the daily protein intake (1.7 g protein x kg FFM(-1) x day(-1)) was either spread over 4 meals in the sp...

Tandem fluorescent protein timers (tFTs) report on protein age through time-dependent change in color, which can be exploited to study protein turnover and trafficking. Each tFT, composed of two fluorescent proteins (FPs) that differ in maturation kinetics, is suited to follow protein dynamics within a specific time range determined by the maturation rates of both FPs. So far, tFTs have been co...