Bioretrosynthesis for the manufacturing of complex molecules from simple substrates

Development of chemical synthetic schemes for a particular molecule is typically carried out in the retrosynthetic fashion by organic chemists. Specifically, organic chemists analysed the chemical structure of the molecule of interest, identify possible reaction schemes capable of generating the various functional groups present in the molecule, and finally sequence the chemical reactions in a … More Bioretrosynthesis for the manufacturing of complex molecules from simple substrates

Cell-free biocatalysis

Enzymes catalysed biochemical reactions and thus biotransformation for producing useful products are commonly carried out using whole cell biocatalysis, where the cell serves as carrier for the enzymes important to converting the substrate to product. However, due to multiple competing reactions in the cell, it is desired to achieve higher productivity and purity of products … More Cell-free biocatalysis

Bottom-up biology illuminating the secrets of life

Biological research is typically pursued using the top-down approach where scientists seek to understand the fundamental underpinnings of life by dissecting the various components of cells using increasingly refined techniques and instruments. However, there is a recent trend of studying the principles that govern cellular processes using bottom-up approaches.   Specifically, in what is known … More Bottom-up biology illuminating the secrets of life

Enzymatic DNA synthesis could help reduce cost of DNA synthesis

Chemical-based DNA synthesis is the critical enabling tool of synthetic biology. Specifically, genes or fragments of DNA could be chemically synthesised using phosphoramidite chemistry for use in applications such as gene cloning; thus, significantly reducing the time and expense needed for molecular cloning. Typically, short fragments of DNA are synthesised which are subsequently stitched into … More Enzymatic DNA synthesis could help reduce cost of DNA synthesis

Metabolic sensor in cells may react to nutritional environment available and decide on growth decision

In microbial ecology, experimental observations of fast-growing microbes able to grow on rich medium at the expense of slow-growing ones suggested that depletion of nutrients by fast-growers and subsequent domination of available agar surface may hamper the growth of slow-growing ones. However, why didn’t the slow-growing microbes also react to the high nutritional content of … More Metabolic sensor in cells may react to nutritional environment available and decide on growth decision

De novo enzyme design achieves good enzymatic activity

Improvement in enzyme activity typically arise from the introduction of mutations into the enzyme’s amino acid sequence. This is followed by a high throughput screen of the mutant enzymes for desired activity levels. Usually, a few mutants with enhanced activity for a given substrate could be obtained. Mutations could be introduced to an enzyme through … More De novo enzyme design achieves good enzymatic activity

Caution should be exercised in interpreting cryo-electron microscopy structures

Cryo-electron microscopy uses snap-freezing to fix the conformations of proteins prior to electron microscopy imaging. From the initial blurry images to high resolution electron density maps that could rival those obtained from X-ray crystallography, cryo-electron microscopy (cryo-EM) has come a long way in terms of innovations in technique and progressive incremental refinements. While the technique … More Caution should be exercised in interpreting cryo-electron microscopy structures

DNA writers for encoding cellular signals into the genome

Myriad cellular signals are generated through various regulatory activities for processes in metabolism and signal transduction. But the challenge has been in understanding these cellular signal transduction events that have largely remained hidden from our view. Using DNA writing technologies, researchers have been able to encode some of these previously hidden intracellular messages and signals … More DNA writers for encoding cellular signals into the genome

Enzyme likely evolved from a high temperature to a low temperature environment

Given that the last universal common ancestor (LUCA) cells likely existed in alkaline hydrothermal vents in the ocean, enzymes that exist by that time in life’s evolution should be ones adapted to high temperature environments. Thus, in progressing from a high to low temperature environment, enzymes likely took a path down the energy ladder in … More Enzyme likely evolved from a high temperature to a low temperature environment

LB Lennox medium is limiting in sugars not nitrogen

LB Lennox medium is commonly used for the cultivation of a variety of microorganisms such as bacteria. Comprising tryptone, yeast extract, and sodium chloride, its provides a rich medium for the cultivation of bacteria to relatively high cell density. However, while the attained cell density may be sufficient for cell biology and molecular biology studies, … More LB Lennox medium is limiting in sugars not nitrogen