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Abstract Soft porous organic crystals with stimuli‐responsive single‐crystal‐to‐single‐crystal (SCSC) transformations are important tools for unraveling their structural transformations at the molecular level, which is of crucial importance for the rapid development of stimuli‐responsive systems. Carefully balancing the crystallinity and flexibility of materials is the prerequisite to construct advanced organic crystals with SCSC, which remains challenging. Herein, a squaraine‐based soft porous organic crystal (SPOC‐SQ) with multiple gas‐induced SCSC transformations and temperature‐regulated gate‐opening adsorption of various C1‐C3 hydrocarbons is reported. SPOC‐SQ is featured with both crystallinity and flexibility, which enable pertaining the single crystallinity of the purely organic framework during accommodating gas molecules and directly unveiling gas‐framework interplays by SCXRD technique. Thanks to the excellent softness of SPOC‐SQ crystals, multiple metastable single crystals are obtained after gas removals, which demonstrates a molecular‐scale shape‐memory effect. Benefiting from the single crystallinity, the molecule‐level structural evolutions of the SPOC‐SQ crystal framework during gas departure are uncovered. With the unique temperature‐dependent gate‐opening structural transformations, SPOC‐SQ exhibits distinctly different absorption behaviors towards C3H6 and C3H8, and highly efficient and selective separation of C3H6/C3H8 (v/v, 50/50) is achieved at 273 K. Such advanced soft porous organic crystals are of both theoretical values and practical implications.

Abstract A weak codon usage bias was found in Dendrobium catenatum (D. officiale) antimicrobial peptides (AMPs), after the analysis of relative synonymous codon usage, GC contents, and the effective number of codons. The codon usage preference was mainly influenced by natural selection pressure. The self‐optimized prediction method and SWISS‐MODEL were applied for peptide structural and domain analyses, and some typical antimicrobial domains were found in D. officinale AMP amino sequences, such as knot1 domain, gibberellins‐stimulated domain, cupin_1 domain, defensin_like domain, and SLR1‐BP (S locus‐related glycoprotein 1 binding pollen coat protein) domain. To investigate the AMPs gene expression pattern, abiotic stresses, such as salt stress, drought stress, salicylic acid (SA), and methyl jasmonate (JA), were applied and the gene expression levels were detected by the real‐time fluorescent quantitative polymerase chain reaction. Results showed that, even though the basic AMPs gene expressions were low, some AMPs can still be induced by salt dress, while the drought dress did not show the same impact. The SA and JA signaling pathways might be involved in most of the AMPs expressions. The natural selection of the D. officinale AMPs and thus forming diverse types of AMPs enhanced the plant's innate immunity and disease resistance capability, which would lead to a better understanding of the molecular mechanism for D. officinale adapting to the environment. The finding that salt stress, SA, and JA signaling pathways can induce AMP expression lays a foundation for the further development and functional verification of D. officinale AMPs.