Isolation and characterization of a novel endo-beta-1, 4-glucanase from a metagenomic library of the black-goat rumen

ABSTRACT The various types of lignocellulosic biomass found in plants comprise the most abundant renewable bioresources on Earth. In this study, the ruminal microbial ecosystem of black goats was explored because of their strong ability to digest lignocellulosic forage. A metagenomic fosmid library containing 115,200 clones was prepared from the black-goat rumen and screened for a novel cellulolytic enzyme. The KG35 gene, containing a novel glycosyl hydrolase family 5 cellulase domain, was isolated and functionally characterized. The novel glycosyl hydrolase family 5 cellulase gene is composed of a 963-bp open reading frame encoding a protein of 320 amino acid residues (35.1 kDa). The deduced amino acid sequence showed the highest sequence identity (58%) for sequences from the glycosyl hydrolase family 5 cellulases. The novel glycosyl hydrolase family 5 cellulase gene was overexpressed in Escherichia coli. Substrate specificity analysis revealed that this recombinant glycosyl hydrolase family 5 cellulase functions as an endo-β-1,4-glucanase. The recombinant KG35 endo-β-1,4-glucanase showed optimal activity within the range of 30-50 °C at a pH of 6-7. The thermostability was retained and the pH was stable in the range of 30-50 °C at a pH of 5-7.

Evaluation of plasma leptin levels & BMI as predictor of postpartum weight retention.

Background & objectives: Plasma leptin level during pregnancy has been reported as a biochemical predictor of postpartum weight retention. The objective of this study was to determine the relationship between pregnancy-related factors including plasma leptin and postpartum weight retention in Korean women. Methods: A convenience sampling method was used among women attending a high-risk pregnancy clinic in Pusan National University Hospital, Busan, between March 2002 and February 2003. We investigated 75 women during pregnancy and 6 months postpartum. Plasma leptin levels were measured using an ELISA. The weight gain during pregnancy and postpartum weight retention, and the correlation between the plasma leptin levels and body weight were evaluated. Results: The plasma leptin levels at the 1st trimester and body weight at 24 wk of gestation, 6 wk, and 6 months postpartum differed significantly between the underweight and overweight groups and between the normal and overweight groups. Plasma leptin levels during the first trimester correlated with the initial BMI at first visit and term, and body weight at term, while the initial BMI significantly correlated with the body weight at term, 6 months postpartum, and 6 months postpartum. Interpretation & conclusions: Our findings suggest that the plasma leptin level in the first trimester is a predictor of maternal weight at term, while initial BMI is a better predictor of maternal weight at 6 wk and 6 months postpartum. Further, postpartum weight retention was more dependent on first pre-natal visit factors rather than weight changes during pregnancy. Anthropometric measures at first pre-natal visit to prevent postpartum obesity can be recommended.

Evaluation of plasma leptin levels & BMI as predictor of postpartum weight retention.

BACKGROUND & OBJECTIVE: Plasma leptin level during pregnancy has been reported as a biochemical predictor of postpartum weight retention. The objective of this study was to determine the relationship between pregnancy-related factors including plasma leptin and postpartum weight retention in Korean women. METHODS: A convenience sampling method was used among women attending a high-risk pregnancy clinic in Pusan National University Hospital, Busan, between March 2002 and February 2003. We investigated 75 women during pregnancy and 6 months postpartum. Plasma leptin levels were measured using an ELISA. The weight gain during pregnancy and postpartum weight retention, and the correlation between the plasma leptin levels and body weight were evaluated. RESULTS: The plasma leptin levels at the 1(st) trimester and body weight at 24 wk of gestation, 6 wk, and 6 months postpartum differed significantly between the underweight and overweight groups and between the normal and overweight groups. Plasma leptin levels during the first trimester correlated with the initial BMI at first visit and term, and body weight at term, while the initial BMI significantly correlated with the body weight at term, 6 months postpartum, and 6 months postpartum. INTERPRETATION & CONCLUSION: Our findings suggest that the plasma leptin level in the first trimester is a predictor of maternal weight at term, while initial BMI is a better predictor of maternal weight at 6 wk and 6 months postpartum. Further, postpartum weight retention was more dependent on first pre-natal visit factors rather than weight changes during pregnancy. Anthropometric measures at first pre-natal visit to prevent postpartum obesity can be recommended.