PMID: 36921May 23, 1979

Purification and preliminary characterization of two asclepains from the latex of Asclepias syriaca L. (milkweed)

Biochimica Et Biophysica Acta
W J Brockbank, K R Lynn


Two groups of asclepains have been isolated from Asclepias syriaca L. (milk-weed) latex and a representative of each has been purified. Asclepains A3 and B5 are homogeneous proteins with molecular weights of 23 000 and 21 000, respectively. Both require a reducing and chelating agent for maximum activity and hydrolyze ester, amide and peptide bonds. The optimum pH for hydrolysis of casein is 7.5 to 8.5 for asclepain A3 and 7.0 to 7.5 for asclepain B5. Both enzymes are autolytic when active and are inhibited by p-chloromercuribenzoate, iodoacetic acid and sodium tetrathionate. Asclepains A3 and B5 each contain one titratable SH group per molecule and no bound carbohydrate. Each of the two enzymes has leucine as the N-terminal amino acid. There are notable differences in their amino acid compositions.


Feb 20, 2003·Phytochemistry·Vikash Kumar Dubey, M V Jagannadham
Mar 21, 1998·Bioscience, Biotechnology, and Biochemistry·H YonezawaT Uchikoba
Feb 8, 2016·Applied Biochemistry and Biotechnology·Cynthia SequeirosSebastián A Trejo
Sep 13, 2006·International Journal of Experimental Pathology·Gillian StepekJerzy M Behnke
Aug 21, 1980·Biochimica Et Biophysica Acta·K R LynnC Roy
Nov 15, 1982·Journal of Molecular Biology·U HeinemannW Saenger

Related Concepts

Peptide Hydrolases
Substrate Specificity
Hydrogen-Ion Concentration
Cysteine Hydrochloride

Trending Feeds


Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Synapse Loss as Therapeutic Target in MS

As we age, the number of synapses present in the human brain starts to decline, but in neurodegenerative diseases this occurs at an accelerated rate. In MS, it has been shown that there is a reduction in synaptic density, which presents a potential target for treatment. Here is the latest research on synapse loss as a therapeutic target in MS.

Artificial Intelligence in Cardiac Imaging

Artificial intelligence (ai) techniques are increasingly applied to cardiovascular (cv) medicine in cardiac imaging analysis. Here is the latest research.

Position Effect Variegation

Position Effect Variagation occurs when a gene is inactivated due to its positioning near heterochromatic regions within a chromosome. Discover the latest research on Position Effect Variagation here.

Social Learning

Social learning involves learning new behaviors through observation, imitation and modeling. Follow this feed to stay up to date on the latest research.

Cell Atlas of the Human Eye

Constructing a cell atlas of the human eye will require transcriptomic and histologic analysis over the lifespan. This understanding will aid in the study of development and disease. Find the latest research pertaining to the Cell Atlas of the Human Eye here.

Single Cell Chromatin Profiling

Techniques like ATAC-seq and CUT&Tag have the potential to allow single cell profiling of chromatin accessibility, histones, and TFs. This will provide novel insight into cellular heterogeneity and cell states. Discover the latest research on single cell chromatin profiling here.

Genetic Screens in iPSC-derived Brain Cells

Genetic screening is a critical tool that can be employed to define and understand gene function and interaction. This feed focuses on genetic screens conducted using induced pluripotent stem cell (iPSC)-derived brain cells.