6-Phytase/genetics; Acid Phosphatase/genetics; Bacterial Proteins/genetics; Escherichia coli/metabolism; Genes, Bacterial; Pichia/metabolism; Shigella/enzymology; 6-Phytase/antagonists & inhibitors; 6-Phytase/chemistry; 6-Phytase/isolation & purification; 6-Phytase/metabolism; Acid Phosphatase/antagonists & inhibitors; Acid Phosphatase/chemistry; Acid Phosphatase/isolation & purification; Acid Phosphatase/metabolism; Amino Acid Sequence; Bacterial Proteins/antagonists & inhibitors; Bacterial Proteins/isolation & purification; Bacterial Proteins/metabolism; Base Sequence; Citrobacter/enzymology; Cloning, Molecular/methods; Escherichia coli/enzymology; Escherichia coli Proteins/chemistry; Gene Expression Regulation, Bacterial; Gene Expression Regulation, Fungal; Glycosylation; Molecular Sequence Data; Phylogeny; Phytic Acid/metabolism; Protein Processing, Post-Translational; Protein Stability; Recombinant Fusion Proteins/metabolism; Sequence Alignment; Sequence Homology, Amino Acid; Shigella/genetics; Species Specificity; Spheroplasts; Substrate Specificity; Temperature; Trypsin/pharmacology