Lactobacillus helveticus highly active esterase. hydrolyzes chlorogenic acid
Comment
one of the most active CGA esterases known to date with a Km of 0.090 mM and a kcat of 82.1 s-1. Other strains: Lactobacillus helveticus (Lactobacillus suntoryeus) ( DPC 4571; CIRM-BIA 951)
(Below N is a link to NCBI taxonomic web page and E link to ESTHER at designed phylum.) > cellular organisms: NE > Bacteria: NE > Terrabacteria group: NE > Firmicutes: NE > Bacilli: NE > Lactobacillales: NE > Lactobacillaceae: NE > Lactobacillus: NE > Lactobacillus helveticus: NE
Warning: This entry is a compilation of different species or line or strain with more than 90% amino acid identity. You can retrieve all strain data
(Below N is a link to NCBI taxonomic web page and E link to ESTHER at designed phylum.) Lactobacillus helveticus CNRZ32: N, E.
Lactobacillus helveticus CIRM-BIA 951: N, E.
Lactobacillus helveticus DPC 4571: N, E.
Lactobacillus helveticus CIRM-BIA 953: N, E.
Lactobacillus helveticus CIRM-BIA 101: N, E.
Lactobacillus helveticus H9: N, E.
Lactobacillus helveticus MTCC 5463: N, E.
Lactobacillus helveticus CIRM-BIA 104: N, E.
Lactobacillus helveticus DSM 20075: N, E.
Lactobacillus helveticus CIRM-BIA 103: N, E.
Lactobacillus helveticus H10: N, E.
Lactobacillus helveticus R0052: N, E.
Lactobacillus helveticus DSM 20075 = CGMCC 1.1877: N, E.
MSRITIERDGLTLVGDREEPFGEIYDMAIIMHGFAANRNTDLLRQIADDL
RDENVASVRFDFNGHGESDGKFEDMTVCNEIADGKAILDYVRTDPHVRDI
FLVGHSQGGVVASMLAGLYPDVVKKVVLLAPAAQLKDDALRSNTQGATYD
PNHIPDVVPLVGNKLGMKLGGFYLRTAQVLPIYEVSQCFTRPVSVIAGTN
DQVVDPKYAKKYDEVYENSELHMIPNADHRFSGGYKDMAADLTAQFLKPA
F
LegendThis sequence has been compared to family alignement (MSA) red => minority aminoacid blue => majority aminoacid color intensity => conservation rate title => sequence position(MSA position)aminoacid rate Catalytic site Catalytic site in the MSA MSRITIERDGLTLVGDREEPFGEIYDMAIIMHGFAANRNTDLLRQIADDL RDENVASVRFDFNGHGESDGKFEDMTVCNEIADGKAILDYVRTDPHVRDI FLVGHSQGGVVASMLAGLYPDVVKKVVLLAPAAQLKDDALRSNTQGATYD PNHIPDVVPLVGNKLGMKLGGFYLRTAQVLPIYEVSQCFTRPVSVIAGTN DQVVDPKYAKKYDEVYENSELHMIPNADHRFSGGYKDMAADLTAQFLKPA F
Chlorogenic acid esterases (ChlEs) are a useful class of enzymes that hydrolyze chlorogenic acid (CGA) into caffeic and quinic acid. ChlEs can break down CGA in foods to improve their sensory properties and release caffeic acid in the digestive system to improve the absorption of bioactive compounds. This work presents the structure, molecular dynamics, and biochemical characterization of a ChlE from Lactobacillus helveticus (Lh). Molecular dynamics simulations suggest that substrate access to the active site of LhChlE is modulated by two hairpin loops above the active site. Docking simulations and mutational analysis suggest that two residues within the loops, Gln(145) and Lys(164) , are important for CGA binding. Lys(164) provides a slight substrate preference for CGA, whereas Gln(145) is required for efficient turnover. This work is the first to examine the dynamics of a bacterial ChlE and provides insights on the substrate binding preference and turnover in this type of enzyme.
Chlorogenic acid (CGA) is an ester between caffeic and quinic acid. It is found in many foods and reacts with free amino groups in proteins at alkaline pH, leading to the formation of an undesirable green pigment in sunflower seed-derived ingredients. This paper presents the biochemical characterization and application of a highly active chlorogenic acid esterase from Lactobacillus helveticus. The enzyme is one of the most active CGA esterases known to date with a K(m) of 0.090smM and a k(cat) of 82.1ss(-1). The CGA esterase is easily expressed recombinantly in E. coli in large yields and is stable over a wide range of pH and temperatures. We characterized CGA esterase's kinetic properties in sunflower meal and demonstrated that the enzyme completely hydrolyzes CGA in the meal. Finally, we showed that CGA esterase treatment of sunflower seed meal enables the production of pale brown sunflower protein isolates using alkaline extraction. This work will allow for more widespread use of sunflower-derived products in applications where neutrally-colored food products are desired.
A high variety of plants that are used for food production contain esterified hydroxycinnamic acids. As their free forms display several benefits, like an enhanced absorption in human intestinal tract, anti-oxidative and anti-carcinogenic effects, an improved protein solubility and reduced discoloration, the microbial ability to cleave the ester bond is highly desired. In order to examine potential fermentation strains for this purpose, six different lactic acid bacteria and one bifidobacterial strain were screened for their ability to degrade esterified hydroxycinnamic acids because these strains are commonly used for fermentation of plant-based foods. Moreover, their cinnamoyl esterase activity was examined by molecular biological analyses. The enzymes were heterologously expressed in Escherichia coli, purified and biochemically characterized. The purified esterases with a molecular mass around 27-29 kDa had their optimum predominantly between pH 7 and 8 at 20-30 degreesC. Bifidobacterium animalis subsp. lactis, Lactobacillus gasseri, Lactobacillus acidophilus, Lactobacillus plantarum and Lactobacillus fermentum displayed activities against a broad substrate range (methyl caffeate, methyl trans-p-coumarate, chlorogenic acid as well as partially ethyl ferulate). Concerning substrate affinity, reaction velocity, thermal and pH stability, Lactobacillus gasseri showed the overall best performance. The herein studied lactic acid- and bifidobacteria are promising for the production of fermented plant-based foods with an increased quality and nutritional value.
Lactobacillus helveticus highly active esterase. hydrolyzes chlorogenic acid
